Why does speed matter?

Consumers increasingly rely on the web to access digital content and services. If you look at your website's analytics, you can probably see this story playing out in your own data. Consumers are also more demanding than they've ever been, and when they experience your website, they aren't only comparing you with your competitors, they're rating you against the best-in-class services they use every day.

This post rounds up some of the research that has been done on the relationship between performance and business success, and why speed is one of the defining factors in how successful online ventures can be.

Performance is about retaining users

Thanks to the collaboration with Google and the introduction of LCP as the main KPI for page performance, it was possible to significantly improve the customer experience of our ecommerce.


Performance plays a vital role in the success of any online venture. Websites that load quickly and respond to user input in a timely fashion engage and retain users better than websites that are slow to load, and feel sluggish.

At Google, we have spent considerable time and effort defining a set of user-centric performance metrics known as Core Web Vitals. While there are many Core Web Vitals case studies on this website highlighting the connection between performance and business outcomes, here are a couple for you to consider:

Studies have also shown the negative impact that poor performance can have on business outcomes. As an example, the BBC found they lost an additional 10% of users for every additional second their site took to load. If you care about retaining users, then you should be focusing on performance!

Performance is about improving conversions

While retaining users is crucial to improving conversions, performance can also have a material effect on whether your website's users follow through. Slow sites have a negative impact on revenue, and fast sites are shown to increase conversion rates and improve business outcomes, as these select case studies can attest to:

The relationship between performance and business outcomes is clear: if you have an online business, performance is something you should be prioritizing if you're not already—it's likely that your competitors are!

Performance is about the user experience

Performance isn't just about business outcomes. When it comes to the user experience, speed matters. A consumer study showed that the stress response to delays in page speed are similar to that of watching a horror movie or solving a mathematical problem, and greater than waiting in a checkout line at a retail store.

As a page begins to load, there's a period of time where users wait for content to appear. Until this happens, there's no user experience to speak of. This lack of an experience is fleeting on fast connections. On slower connections, however, users are forced to wait. Users may experience more challenges as page resources slowly trickle in.

A comparison of two filmstrip reels of a page loading. The first shows a page loading on a slow connection, while the second shows the same page loading on a fast connection.
A comparison of page load on a very slow connection (top) versus a faster connection (bottom).

Performance is a foundational aspect of good user experiences. When sites ship lots of code, browsers must use megabytes of the user's data plan to download it. Mobile devices in particular have limited CPU power and memory. This can create poor performance conditions, and—knowing human behavior—people can only tolerate adverse conditions on a website for so long before abandoning it.

Get started with improving your website's performance

Now that you know the real costs of websites that fail to engage and retain users, you're likely ready to do what it takes to make your website faster so that you can achieve your goals. Learn Performance is a course that is designed to help those new to web performance, and goes through the fundamentals of improving performance by covering a variety of topics.

If you're ready to Learn Performance, then your journey starts by learning the general considerations of HTML and performance. From there, additional modules delve further into performance as it pertains to a number of different aspects of web development. By the time you reach the end of this course, you'll have what it takes to make your corner of the web faster for all who use it!