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The Illusion of Speed


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[This is a guest blog post authored by Joe Baz (@joebaz) is the CEO & Founder of Above the Fold, a user experience design company.]

?Perception is reality.? This adage is particularly true when it comes to managing the performance of a website, mobile app or software application. (For the sake of simplicity, I?ll refer to these as sites.) Perceived time can be very different from the actual time an action requires, but a well-engineered, engrossing experience results in a positive perception. Whether or not we are even aware of our perceptions, (and we?ve all waited as five minutes becomes fifteen, or been blissfully unaware as an hour passes in minutes) we process these ?illusions of time,? if you will, on a daily basis.

Perception is a faculty of our neuromuscular system1, and it allows us to manage time, which is an essential ingredient for functioning in our daily lives. Time is so important that it is generally referred to as ?a precious commodity.? It?s because of this importance that actual speed is not the sole factor in what we perceive as being fast, but rather that our definition of ?fast? correlates directly to whether or not our time has been wasted.

Managing Time

How do we understand and manage time? Fortunately, our brain is hardwired to grasp the concept of time. Here are
three mechanisms that explain how:

  • Association: What past experiences influence your attitude about future experiences? By answering this question of perception, we can judge whether or not the information we are seeing is relevant and valuable, based on our experiences. Perhaps our prior knowledge2 tells us mobile websites are “too slow.” This could be because most of us are on a 3G network or because the site owner has very large graphics or objects that need to be loaded. Regardless of the reason, a negative (or positive) association conditions us to assume similar experiences will carry the frustrations (or delights). Long term, this can lead to changes in behavior ? if we perceive mobile websites to be ?too slow? we may be more inclined to download a native app instead.
  • Estimation: We estimate time constantly, from when we?re telling our spouses how much longer we will be at work, to what our ETA is when we are running late. There is almost always a basis (i.e. “past experience”) for which we derive our estimations.3 And, sometimes our estimations are influenced by ulterior motives. I may intentionally overestimate my ETA so that my fiance won’t disown me. 😉 Estimation is relevant to performance since it allows us to judge whether or not it is worth investing our energy into a task given our current time constraints.
  • Expectation:In the context of perception, forming expectations allows us to evaluate time in respect to pleasure.When we feel pleasure as a result of an activity, we don’t notice time. Conversely, when we feel discontent as a result of an activity, we feel that we’ve wasted time. In fact, in a study conducted by UIE, was rated by users as the slowest site, even though the site was actually the fastest with an average load time of 8 seconds; however,, which was rated the fastest by the users, was by far the slowest site with an average load time of 36 seconds4 . “(The concept of Expectation has come a long way since the days of dial up!)”, however, provided more pleasure and more reward. In regard to performance, we have an expectation of accomplishing our goal as quickly as possible, and making the best use of our time

Altering Time

Given these three mechanisms, we can carefully craft illusions that will alleviate the pain of wasted time on sites. More specifically, we can use certain techniques to manipulate the perception of time for the end user.


One caveat: I’m not suggesting that these techniques supersede actual site performance optimization; rather these techniques should be considered and implemented during the process of optimization.

Magician Horace Goldin is best known for his magic act of sawing a woman in half and the same magic can apply it to your site:

  • For information-rich sites, start by cutting the content in half. Consider how the information will be consumed across the entire lifecycle of your customer?s experience, not just in one viewing (i.e. page.) You can break the content over additional pages or cut unnecessary content altogether.
  • If you have a software product, consider only supporting the features that are critical to the customer. Alternatively, consider branching your site into a separate app to target a different customer segment. This approach is typically referred to as MVP, or Minimum Viable Product.

This technique of cutting down improves the user’s perception by reducing information overload. For those without prior knowledge of your product or who have a low working memory capacity, this is especially helpful5 . Most importantly, trimming down content and features will appease their association and expectation faculties. Users are constantly sifting through noise and fluff to find the information and user interfaces most relevant to them.The faster we help users find what they need, the greater likelihood they will perceive the site as being fast6 . I attribute part of Google?s search engine success to MVP; they kept it simple while all other search engines were loading up their sites with features and content irrelevant to search.


Sleight of hand is essential in manipulating our perception of time in a positive way. For magicians, sleight-of-hand is all about attracting the eye. It”s how the hands move that creates the effect of the illusion; while attracting the eye with one hand, the magician can complete the trick with the other. In the online world, this is best demonstrated through the progress bar experiment7 conducted by Chris Harrison.

Progress Bar for DownloadIn the experiment, various progress bar animations were tested. The fastest one perceived by the user was the one that many Mac users are accustomed to: a ripple effect animation that moves in the opposite direction of the progress bar

This technique aids the user by reducing the anxiety in long downloading or processing time. It makes the process seem faster because the motion of ripple effect (the hand doing the attracting) speaks to our association and estimation faculties. Netflix pulls this same technique off quite effectively; their movie ?pre-loading? screen is actually a static image of the loading screen at ?7% complete,? creating the illusion that the movie has already begun to load. In both these examples the user is attracted to an illusion of further or continued progress while the back end processes at a slower pace.

The sleight-of-hand is by far one of the hardest techniques to master. Every interaction design needs to be crafted and tested against user associations and expectations. One size does not fit all!

Seeing is Believing

One of the most important ways we can achieve an increase in site performance is through increased site usability. That is, create your site to allow the user to accomplish her task as quickly and effortlessly as possible. When the user completes her goal, she is not only satisfied, but perceives the experience as being fast because her time has been valued. (Again, actual site performance is equally important.)

To test users? perceptions of site time, here is a high level A/B test plan to follow:

  • Begin with both your current design and your new proposed design.
  • Setup both designs so that that they load in exactly the same amount of time.
  • Create one task and split the users into two control groups: Group A tests the current design while group B tests the new design.
  • At the end of each task, ask the user, you will want to ask two questions:
    • “On a scale of 1 to 10, how would you rate the speed of the site?”
    • “Why do you feel the site is [fast/slow]?”

You can run this test with many users in a few hours, gaining insight into your users? perceptions, and practicing your skill as an illusionist. From here it?s easy to begin adjusting to make your site perform better? or so your users will think!


Whether you are a UX professional, a product manager or someone who just wants to create a faster site for your customers, it’s important to recognize how the mind works and to test how users react to visual stimulus. A simple plan is to practice creating illusions in your designs, conduct regular usability tests, and take measures to keep your site operating smoothly. Through these steps you will foster a user experience that will leave your audience with a feeling of comfort and delight. Only then can you call yourself an illusionist.

Author: Joe Baz (@joebaz) is the CEO & Founder of Above the Fold, a user experience design company in downtown Boston, which specializes in UI design, prototyping, usability testing and analytics.


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