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Optimising your website performance can be a great way to improve the user experience

Many things shape the experience of users. However, nothing is more likely to drive users away than a poorly performing website.

We like to think of ourselves as guardians of the user experience. Why then, when we talk to clients, do we tend to neglect the non-visual elements that have a profound effect on the experience. Clients love beautiful pictures, and as designers, we do nothing to dissuade them.

In fact, in many ways, developers have a greater impact on the experience than we do. Look at the role of performance in the user experience. Still, we do not tend to talk about that with clients. We know they will not be interested and we are not willing to put the hard work in to convince them to care. However, we should.

After all a slow website:

  • damages findability,
  • increases the time to complete a task,
  • reduces user satisfaction,
  • endangers accessibility,
  • undermines understanding of your products and services.

Still not sure you can convince clients to take performance seriously? Okay, let's look a little deeper.


1. Poor performance damages findability

Google has made their position over site performance clear. The faster the site, the better the ranking, especially on mobile.

Findability is a compelling argument to make for performance with clients. They care about their rankings, and we care about users finding the content they need.

However, that is not the only reason a client should care.

Google have made it clear they consider performance critical.


2. Poor performance increases the time to complete a task

The longer it takes a user to do something the more likely they are to give up. That damages conversion rates.

A one-second delay in load time leads to a 7% drop in conversion and an 11% fewer page views. In fact, a staggering 1 in 4 people will abandon a page that takes longer than 4 seconds to load. What is more, things are even worse on mobile with 74% of users giving up if a page takes 5 seconds or more to load. (Source)

Poor performance has a significant effect on conversion and page views.

Each new page that a user has to visit to complete a task only exacerbates this problem, something that also provides an opportunity. With users so biased towards fast loading pages, a site optimised for speed has a competitive advantage.

However, this is not only about conversion; it is also about perceptions.


3. Poor performance reduces user satisfaction

Users have a more positive feeling about fast loading pages. A fast website gives a sense of progress. The user feels they are moving quickly towards their goal and that increases satisfaction, another metric your clients should consider.

A 1-second delay in page load will decrease customer satisfaction by about 16%. Worst still 79% of users who are dissatisfied with a website’s performance are less likely to buy from the same site again. (Source)

However, poor performance and reduced satisfaction will not only damage customer satisfaction. They also have a knock on effect. They hurt your brand as a whole. That is because 44% of users will tell their friends about a bad experience online.

Poor performance can drive users away and damage your brand.

Of course, none of this is an issue if the user is unable to access the content at all.


4. Poor performance endangers accessibility

Performance is not just a conversion issue. It is about more than users being impatient. It can prevent users accessing your content. A poor performing website can timeout preventing the page loading. Even a failure of a web font or javascript file to load can make content inaccessible. These failures are why progressive enhancement is still important, despite claims otherwise.

Performance is a particular problem over cellular connections or in developing countries. Then, of course, there is the dreaded hotel wifi or rural areas where connectivity is slow.

Finally, there are those using assistive technologies like screen readers or those with cognitive disabilities. These people are particularly sensitive to performance issues. The temptation is to dismiss these audiences, but remember, these people have significant spending power.

In fact research indicates UK retailers could be missing out on £11.75bn in revenue by ignoring the needs of disabled users. Nearly three-quarters of disabled online consumers (71%) will click away from websites that they find difficult to use due to the effect of their disability.

However, that is not all. Poor performance also threatens a user's understanding of your products and services.


5. Poor performance undermines understanding

According to Aberdeen Group, each 1 second added to load time leads to users viewing 11% fewer pages. The fewer pages users visit, the less understanding they have of your products or services. Poor understanding means that they could miss important information. Information about the product that can cause all kinds of problems further down the line.

I am not just talking about lost sales either. For example, if a user misses some important aspect of what you are going to deliver, it could lead to increased support costs and more returns. These are factors that erode profit margins.

This kind of confusion also has knock-on effects. It further lowers satisfaction and leads to misinformation about your products beyond your site.


A no-brainer!

I would hope by now the benefits of focusing on performance are clear. It not only improves the user experience, but it also makes sound business sense. In fact, if I had a choice between improving a user interface or increasing performance I would focus on performance. That is because poor performance has the potential to undermine every aspect of the experience, while the user interface focuses primarily on usability and brand perception.

Don’t misunderstand me; visual design matters a lot. I know some of you will disagree with my assessment and in truth, it is not as black and white as I am painting it. What I am trying to drive home is that we should not treat performance as a second class citizen just because we cannot see the results of time invested in it in the same way. What happens behind the scenes is just as important as the visuals and we need to persuade clients of that.

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