2 ms·
Part of the problem is that they place high importance on the first contentful paint (aka FCP) above all else. They're not very much looking at how it performs
by jfoster 7y ago
Part of the problem is that they place high importance on the first contentful paint (aka FCP) above all else. They're not very much looking at how it performs overall, mostly just how long it takes for a user to see the first bit of content. If that were a bit of text that said "loading" with a spinner that goes for a minute or two, they may consider that fast.
- kaycebasques 7y agoThis section shows how Lighthouse calculates your overall Performance score: https://web.dev/performance-scoring/#lighthouse-6 https://web.dev/performance-scoring/#lighthouse-6 (Note that the table gets cut off on narrow mobile screens... I’ll file a bug) FCP is 20% of the score. The other metrics capture different milestones in the loading experience. For example Total Blocking Time is intended to bring awareness to sites that may look complete but can’t respond to user input (because the main thread is busy running JS). The metrics overview that we just launched provides more detail about how our metrics were designed to capture the end-to-end loading experience (or at least that’s what we’re working towards): https://web.dev/user-centric-performance-metrics/ https://web.dev/user-centric-performance-metrics/ So in the case of your site-that-just-loads-a-spinner example, yes it might have a good FCP time, but it’s LCP time probably wouldn’t be that good, and therefore the overall Performance score would be mediocre. Long story short, I don’t think it’s as easy to game a good Performance score as you might think Disclosure: I work on web.dev