Multiplicative effect of fast-loading websites
Business summary: Website speed-up can massively boost conversion rate and affects SEO, UX and PPC.
Hundreds of studies and articles describe the importance of having fast-loaded websites. No doubts about it. The consequences of it are probably far more extensive, than it might seem. Many discussions have been around about what does it mean that the page is loaded. Is it more important to have the page usable or to have it fully loaded? I would say both. We all know what technical improvements should be done in order to provide seamless user experience (and generate money at first place), but this isn't what this post is about. So, let's keep aside things like cache enabling, code minifying, image compression or redirects reduction.
Site speed affects each and every marketing discipline. Let's focus on what everything is included in it and can be improved.
It's well known that at least Google will generously reward you for fast website and will prefer you in SERP. The first thing that of course will happen is higher organic traffic. Even more interesting part comes when you'll decide to create AMP version of your website. Be prepared for massive increase in organic traffic. It's not an exception that you'll increase in tens of percent! Probably one of the best direct business affecting SEO technique. Another nice thing is that it helps in crawl budget optimization. Crawler will simply digest more of your pages :). At this point the fully loaded page matters more just because the robot evaluates it.
UX is sometimes about trying not to piss off your website visitors. And slowly loaded page is the first touchpoint when you can piss them off very easily. Especially on mobile phones. Just check what is your percentage of mobile traffic and how it grows in time. At first place, if you improve it, you basically stop losing significant volume of users even before they could start browsing. Secondly, you'll lower your bounce rate which will bring more users to at least second page :) and thirdly once your customers buy quickly and easily, the chance they will buy again and become loyal is at least slightly higher. Quite easy and effective part of CRO, I would say. It's not necessary to have the page fully loaded and what's more important is to have the page usable as quickly as possible. At least try to optimize hero elements and load them instantly.
The way automatic bidding algorithms work is that they take your general website performance (conversion rate) into consideration and based on it somehow optimize the bidding strategy. The simple rule applies: the better the general performance, the better paid performance and spend effectivity. Again, just check how much of your traffic is paid to see how much of it can be affected.
The whole point is to understand how many things will change once you improve site speed. If you multiply them all, your final BUSINESS OUTCOME can be impressive. If you will have to explain to your boss or client why you should do that in one sentence, tell them: we'll get more traffic which we'll be able to convert better.
Happy site-speeding :)