The Psychology Behind High Converting Sites

by Peter Boyle

Last updated on July 27th, 2017

We all know the basics by now, right?

Create a headline that hooks attention, display value with your CTAs, reduce distractions, simplify your pages so on and so forth.

They’re actions well documented on sites like this and something we all know are conducive to better conversions. But there’s a problem, too many CROs are dependent on the test results others achieve.

They wait for someone to post a new case study, jump on the bandwagon and follow their example – all the while crossing their fingers and hoping they achieve the same result.

You may well see a good little lift from copying someone else’s test. But that’s not what CRO is about.

You shouldn’t have to wait around for one of the handful of authority figures to make the next big discovery. The success of your business won’t wait on the actions of someone else. You need to take action and see what changes you can implement for a positive change.

“But Pete” you say, “I need these people. I understand the actions that bring conversion lifts, but I don’t understand why they work”.

Well, this article is for you.

I’m going to run through some of the biggest psychological theories that the conversion tactics you know and love are based upon. By diving into the psychology behind high converting sites – you’ll not only understand why certain changes bring about great lifts, but that you’ll also be in a better position to experiment with your own tests.

So let’s get down to understanding the psychology behind CRO and be better positioned to amend our tests. First up….

The Concept of Mental Models

mental Models explanation

Image Credit

The term mental models is widely used in CRO circles. More often than not it refers to a method in which you identify the overlap between key audience needs and the features of your product.

Once identified, you know which key benefits to prominently feature in your landing page copy. It’s a well documented method which has been best covered in the book Mental Models: Aligning Design Strategy with Human Behavior by Indi Young.

Mental Model Diagram

However, whilst you should definitely be familiar with this approach it’s not the definition of mental models I’d like to discuss.

I’m referring to the concept of mental models first mentioned in the 1943 book The Nature of Explanation by psychologist Kenneth Craik. Despite gaining little traction at the time, the concept has recently seen a resurgence in popularity, especially in the field of human-computer interaction (HCI).

When explaining mental models, Craik wrote that the mind creates ‘small-scale models’ of reality that it uses to reason, anticipate events and to underlie explanation. In the simplest of terms, a mental model represents what a user believes about a system or, in the case of CRO, your site/product. The belief that they form is what will influence their decision to purchase.

The problem with mental models is that they’re based on belief, not fact. Even when you display nothing but facts, a users mental model is based upon the way they choose to interpret them.

This is where the problems start. As the site designer, copywriter or product developer you know too much about your product. The way you interpret your copy and site will be completely different to the first time user. This causes a huge disconnect between your mental model and theirs.

Your job is to reduce this disconnect. You need to present the information that highlights benefits in terms the user understands. This helps create of a model that’s conducive to purchasing your product.

But what steps can you take to achieve this? Thankfully, there are a few well known CRO actions perfect for creating a positive mental model.

  • Utilize Social Proof
    • Positive reviews, testimonials or successful case studies all work to present a positive image of your business. On top of this, they’re often written in the words of their peers which lends to their effectiveness and authenticity.
  • Simplify Design/Navigation/Form Fields
    • This advice is most often quoted as successful because it helps the prospect save time. This is most definitely true, especially when you consider the short attention spans of today’s user. However, a quick, easy and pleasant experience fortifies the belief you’re highly organized and effective. A trait we all want in the products we purchase.
  • CTA Placement
    • This is a great example of formatting your site to conform to user’s mental models. The good advice on CTA placement doesn’t advise sticking it above the fold. Better results are achieved when CTAs are placed at positions where the prospect is ready to take action. Basically you’re putting it where users want it to be.

Influencing or aligning with your user’s mental model is pretty much what CRO is all about. Running tests and variations isn’t about seeing which piece of copy performs better, but rather tells you what copy and design elements help build a positive mental model.

Hick’s Law

Hick's Law chart

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Hick’s Law describes the time it takes for a person to make a decision in relation to the possible choices they’re presented with. The larger the number of stimuli, the longer it takes for someone to make a decision.

However, what Hick’s Law doesn’t mention is that there is a critical point where the decision becomes too difficult to make. A point where the cost of ensuring you’ve made the right decision outweighs the benefit of actually making it.

It’s the point of analysis paralysis. Bill Watterson summed it up well in the below Calvin and Hobbes strip.

Coming strip explaining hick's Law

It seems counter intuitive, but reducing the options that are available to your prospects can really help with your overall conversions. There are dozens, if not hundreds of stories out there of how companies have successfully implemented Hick’s Law. And we’re not just talking small ecommerce stores either.

Procter and Gamble saw a 10% increase in sales after reducing their Head and Shoulders shampoo line from 26 varieties down to 15. Offering less is a great way to get more.

Law of Prägnanz

Law of Pragnanz explanation

Prägnanz is the German word for pithiness, which in turn means ‘concise and meaningful’.

The Law of Prägnanz is the psychological principle all those articles you read about simplifying your website design and sign up procedures are based upon.

The law basically demonstrates how we prefer designs that are clear, logical and ordered. Our subconscious interprets these simple designs as safer. We’re able to process them in a shorter period of time and they’re less likely to hide any dangerous surprises.

However, the world isn’t made up of safe, simple designs. So how do our brains cope with the complexity of real life? By reorganizing what we see to form a simpler whole. Take a look at the image below and let me know what you see.

Demonstration of Pragnanz

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The image on the left could indeed be a design all it’s own. But it’s cumbersome and unfamiliar to us. Instead of trying to understand it as it is, our brains will simplify it into the most easily understandable format. In this case, an overlapping rectangle, triangle and circle.

This law reinforces the need for simplicity on your site design.

You don’t want your prospects to come to your site and have to reorganize what they’re seeing into the simplest form. This simplification could lead to a disconnect between what you intended to say and how your prospect interprets it. In short, the formation of a negative mental model.

Device Magic achieved a 35% increase in sign ups after they removed an ‘overly technical’ video and simplified the overall layout from their landing page.

Pragnanz in Action


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Keeping things simple not only creates a better user experience but also negates the need for your prospects to simplify your message.

Take a step back from your design or get a fresh pair of eyes to give it a once over. If there’s an area that’s being simplified into the larger whole, there’s the potential for misunderstandings.  Keep your designs simple and there will be no need for your prospect’s brain to simplify them and misinterpret key points.

Freud’s Pleasure Principle

When you think of psychology chances are the name Freud will spring to mind. And with good reason. Freud is one of the most influential psychologists in history.

Whilst I may take issue with some of his beliefs (No one loves their mother that much) you can’t deny the man had a thorough insight into the workings of the human mind.

Of particular note was Freud’s Pleasure Principle. The principle states that there’s a basic human tendency to seek pleasure and avoid pain.

Nothing too surprising in that. The question is how do pleasure and pain fall in with user interaction and your site? Of course you’re not physically harming your audience, nor is there a physical pleasure. Instead of thinking of pleasure and pain as tangible, we should in fact liken them to cost and benefit.

Cost obviously replacing pain with benefit taking the place of pleasure.

The cost to benefit ratio is one well documented in CRO and applies to everything from writing your benefit focused copy to creating killer CTAs.

If you want your prospect to take an action then you have to make the benefit of doing so outweigh the cost.

Does the benefit of your lead magnet outweigh the cost of supplying an email address and running the risk of protracted spam emails? Are your product benefits equal to or greater than the financial cost of the product + shipping?

The benefits of your product can be explained in numerous ways. You’re not just limited to the widely known benefit driven headlines and CTAs. It doesn’t even end at benefits over features in your body copy.

Take a look at your product/service and tell me if the below aren’t also potential benefits for your customers.

  • Guarantees
    • Having security and peace of mind when purchasing is a definite benefit
  • Trust Seals
    • Again with the security and peace of mind
  • 24 Hour Live Chat
    • People want help when they need it. Having it there is a huge benefit

The list goes on and on.

Your primary goal should be to build on Theodore Levitt’s drill analogy, ‘people don’t want to buy a drill, they want to buy a hole’. Drive home the benefit/pleasure of the ‘drill’ by explaining what it can do for your prospects. It doesn’t just drill holes, it offers extra storage space in the form of shelves, a place to hang treasured family photos etc.

After you’ve taken the usual steps of explaining benefit in your copy, headlines and CTAs etc., look at the other actions you can take to tip the benefit/cost ratio in your favor.

Decoy Effect

The Decoy Effect

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Ever notice how service prices are often set out with three separate tiers?

This isn’t to provide the best level of service or even there to cover as many bases as possible. The true reason companies use this three tier system is because it greatly increases the effectiveness of the page and the amount of revenue earned.

How does it work? Well, it’s all down to the decoy effect.

When a prospect is presented with two options they’re forced to make a decision. Do they buy the limited option for less money, or the comprehensive offer for more?

It’s not an easy decision, but more often than not prospects will choose the cheaper of the two.

This is where the decoy option comes in. You’ve two approaches with using a decoy option.

  1. Put a high price on the decoy, making the former high priced option (now the middle option) seem more appealing.
  2. Put a price that’s slightly higher than the now middle option. The pricing and explanation of the new top tier is so skewed that not going for it would be stupid.

An economist by the name Dan Ariely decided to put the decoy effect to the test after stumbling across an ad for a subscription to The Economist.

Dan ran two pricing adverts by students at MIT’s Sloan School of Management. The first test had three subscription models (one being the decoy) whilst the second only had two. Below are the results.

Decoy effect used by the economist

The total money earned from the above test would have been a respectable $11,444.

After removing the decoy option, Dan saw a huge change in purchasing behaviors.

Decoy effect used by the economist

That comes out to $8012. A difference of $3432!

Despite the middle and high options in test one being the same price, the increase in sales comes from a perceived gain in value.

It’s good to see that this is a method that The Economist still uses today!

Decoy effect used by the economist

Psychology Can be a Powerful Tool

We’ve all heard the CRO best practices. Probably a little too often if we’re being honest! Yet simply replicating a test you’ve seen explained on Crazy Egg or some other CRO site isn’t the best way to increase your conversions.

You need to optimize your tests based on your audience. And knowing the basic psychological principles that influence purchasing behavior is the best way for you to see the greatest gains.

Psychology doesn’t have all the answers, but it’s a damn good place to start.



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Peter Boyle

Pete Boyle is a conversion focused copywriter and marketing consultant. He helps brands increase their revenue through compelling copy and smart email campaigns. Click here to connect with Pete or download one of his free marketing guides.


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  1. Josh says:
    November 4, 2015 at 7:32 pm

    Setting up a high converting site is a tedious and continuous drive. There is no shortcut technique. You may find many different tips and practices that you can follow but it is not a definite hit. What will work for one might not work for the other. So you need to understand what you are offering, your target market, competitors, and all other factors surrounding. That and incorporating the usual techniques will help you.

    • Peter Boyle says:
      November 5, 2015 at 5:25 am

      You’re right Josh, it’s a never ending battle.

      Seasonal changes, demographic changes or a change in the market mean that there’s never any one approach that’s good for all situations.

      I think you’ve hit the nail right on the head with your comment. You might be able to copy another person’s approach and see a good lift, but there’s no guarantee.

      You need to optimise for your own audience and how your product helps them. However, understanding what drives people to convert will help you best communicate your product’s individual benefits to your audience.

  2. Ross Simmonds says:
    November 3, 2015 at 3:19 pm

    Great post Peter.

    Loved the reminder surrounding Trust Seals, 24 Hour Live Chats and Guarantees. Such a simple addition to a site but one that can make the world of difference. I’m always surprised when I visit an ecommerce site and don’t see any badges. Another quick and easy win is an SSL certificate (SEO theories aside) – I’ve come across many articles suggesting it can establish a layer of trust and more conversion.

    • Peter Boyle says:
      November 5, 2015 at 5:28 am

      Thanks Ross!

      Yeah, trust seals are hugely important in getting that sale.

      The idea of SSL certificates is pretty interesting. I’ve got to admit they’re not really something I’ve considered before but I’ll definitely be looking into them now!


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