i always found it very weird that too fast load speed has negative effect.
I wonder which parameters do they use? Shall we assume its the same web but just people coming from different connections? Different sites (different domains, different brands) using a similar funnel? Have they optimized in multiple interactions the site, to achieve certain results per visitors? In that case why they did not simply let it run in sessions for the whole bunch of loading segments?
Definitely loading speed is important, but one thing Ive found in thousands of sites, is how problematic cache management is. Many people use set-and-forget policies, is very rare to see a medium-sized (or small-size) site, being e2e constantly monitored for imperfections. Due to cache issues, say that if for some reason, the server had a little hiccup and the hero did not load propertly, it will be cached horrendously for a big amount of visits that will be downloading that cached version from the edge server. Also if you are running WP, updates are a doom for caching, specially automated updates. And if you manage a couple hundred websites by your own, trust me that automating updates is not an option.
Its funny, but I've been specializing in speed metrics for a big while and after some debate with myself, I'm starting to drop any speed improvement measures in many sites just to keep them healthy at no expenses.
In my first answer, I was answering the question
What strategies do you use to optimize speed?
Now I'm answering the topic question
How important is website loading speed for conversions?
Its important, but not as important as many people think. Obviously you cant have a disastrous 10s loading website. But nowadays just holding good practices, you can have a pretty nice load, you can use a CDN just for a couple static elements (not JS or CSS but images and big fatty assets) and get a really nice result in your loading speed, without the drawback of the necessary caching monitoring.
