A fascinating interactive journey through biometrics using your face.
What gets measured gets done. You are what you measure. Measurement eliminates argument. If you work in an environment that puts store in these oft-quoted business adages then I urge you to take a moment to challenge your calculations. Let’s review our metrics to ensure they can stand up and be counted.
I’ve noticed a trend in recent years—a trend that I’ve admittedly been part of myself—where performance-minded developers will rebuild a site and then post a screenshot of their Lighthouse score on social media to show off how fast it is.
But I’m going to respectfully decline Phil’s advice to use any of the RUM analytics providers he recommends that require me to put another
script element on my site. One third-party script is one third-party script too many.
I hadn’t come across this before—run Lighthouse tests on your pages from six different locations around the world at once.
Cloudfare’s alternative to Google Analytics is now available—for free—regardless of whether your a Cloudflare customer or not:
Being privacy-first means we don’t track individual users for the purposes of serving analytics. We don’t use any client-side state (like cookies or localStorage) for analytics purposes. Cloudflare also doesn’t track users over time via their IP address, User Agent string, or any other immutable attributes for the purposes of displaying analytics — we consider “fingerprinting” even more intrusive than cookies, because users have no way to opt out.
Goodhart’s Law applied to Google’s core web vitals:
If developers start to focus solely on Core Web Vitals because it is important for SEO, then some folks will undoubtedly try to game the system.
Personally, my beef with core web vitals is that they introduce even more uneccessary initialisms (see, for example, Harry’s recent post where he uses CWV metrics like LCP, FID, and CLS—alongside TTFB and SI—to look at PLPs, PDPs, and SRPs. I mean, WTF?).
Good point. When we talk about perceived performance, the perception in question is almost always visual. We should think more inclusively than that.
Progressive disclosure interface patterns categorised and evaluated:
- mouseover popups (just say no!),
- new pages,
- scrolling sideways.
I really like the hypertext history invoked in this article.
The piece finishes with a great note on the MacNamara fallacy:
Everyone thinks metrics let us measure results. But, actually, they don’t. They measure only what they are measuring. Engagement, for example, is not something that can be measured, so we use an analogue for it. Time on page. Or clicks.
We often end up measuring what is quick, cheap, and easy to measure. Therefore, few organizations regularly conduct usability testing or customer-satisfaction surveys, but lots use analytics.
Even today, organizations often use clicks as a measure of engagement. So, all too often, they design user interfaces to generate clicks, so the system can measure them.
Pages are often designed so that they’re hard or impossible to read if some dependency fails to load. On a slow connection, it’s quite common for at least one depedency to fail.
Fire up Reader Mode and read this excellent article informed by data from using a typically slow connection in rural USA today. Two findings are:
- A large fraction of the web is unusable on a bad connection. Even on a good (0% packetloss, no ping spike) dialup connection, some sites won’t load.
- Some sites will use a lot of data!
This is going to be so useful for client work at Clearleft—instant snapshots of performance metrics across industries and regions!
See Tammy’s blog post for me details.
Smart advice from Harry on setting performance budgets:
They shouldn’t be aspirational, they should be preventative … my suggestion for setting a budget for any trackable metric is to take the worst data point in the past two weeks and use that as your limit
Time to Interactive (TTI) is the most impactful metric to your performance score.
Therefore, to receive a high PageSpeed score, you will need a speedy TTI measurement.
At a high level, there are two significant factors that hugely influence TTI:
Matt’s publishing a newsletter on the past, present, and future of tracking:
The last 100 years have been a journey to see how to measure ghosts - how to measure the invisible audiences at the end of technological distribution networks. With every decade, these ghosts have come more and more into focus, ending with a the last ten years of social media and digital advertising that has created unimaginable amounts of data about everything we see, read, click and like.
He sees the pendulum swinging the other way now …for those who can afford it:
If there’s one constant in the economics of audience data over the last 100 years, is that we only get free services if we pay for them with our attention. This has been true for commercial radio and television, free newspapers, mobile games and digital content. If we want privacy, we have to pay for it, and not everyone can afford this. Will the right to become a ghost only be for the people with money to buy premium products?
This is a very useful new feature in Calibre, the performance monitoring tool. Now you can get data about just how much third-party scripts are affecting your site’s performance:
The best way of circumventing fear and anxiety around third party script performance is to capture metrics that clearly articulate their performance impact.
Font metrics help the computer determine things like the default spacing between lines, how high or low sub and super scripts should go, and how to align two differently sized pieces of text next to each other.
I like Tim’s definition here:
A performance budget is a clearly defined limit on one or more performance metrics that the team agrees not to exceed, and that is used to guide design and development.
And I agree about the four attributes required for a performance budget to succeed. It must be:
The point is not to let the performance budget try to stand on its own, somewhere hidden in company documentation collecting dust. You need to be proactive about making the budget become a part of your everyday work.
Great ideas from Addy on where to start with creating a performance budget that can act as a red line you don’t want to cross.
If it’s worth getting fast, it’s worth staying fast.
Yes! Yes! Yes!
Our efforts to measure and improve UX are packed with tragically ironic attempts to love our users: we try to find ways to improve our app experiences by bloating them with analytics, split testing, behavioral analysis, and Net Promoter Score popovers. We stack plugins on top of third-party libraries on top of frameworks in the name of making websites “better”—whether it’s something misguided, like adding a carousel to appease some executive’s burning desire to get everything “above the fold,” or something truly intended to help people, like a support chat overlay. Often the net result is a slower page load, a frustrating experience, and/or (usually “and”) a ton of extra code and assets transferred to the browser.
Even tools that are supposed to help measure performance in order to make improvements—like, say, Real User Monitoring—require you to add a script to your web pages …thereby increasing the file size and degrading performance! It’s ironic, in that Alanis Morissette sense of not understanding what irony is.
Stacking tools upon tools may solve our problems, but it’s creating a Jenga tower of problems for our users.
This is a great article about evaluating technology.
Focusing on the median or average is the equivalent of walking around with a pair of blinders on. We’re limiting our perspective and, in the process, missing out on so much crucial detail. By definition, when we make improving the median or average our goal, we are focusing on optimizing for only about half of our sessions.
Tim does the numbers…
By honing in on the 90th—or 95th or similar—we ensure those weaknesses don’t get ignored. Our goal is to optimize the performance of our site for the majority of our users—not just a small subset of them.