I think something is wrong with me then. When I start something early it normally ends up with me losing momentum part way through, stopping for ages, then having to work like mad at the end anyway. That or I end up changing project idea and having to start again. Both of these ended up happening with my dissertation.
Like even when I start stuff at the right time it goes to shit. Somehow when I do stuff last minute it mostly turns out fine.
Procrastination is good, it takes you were you naturally want to be and what you intuitively think is right. Starting early and forcing yourself through things you don't care about is not productive.
But isn't that like making excuses for yourself tho? I usually did the same as the parent commenter did. But if there's an especially critical task that I cannot afford to ignore I use something like pomodoro timer to keep my attention span in check. Barring an external distraction -- getting more of this as I'm getting more senior in my current work + kids when working remotely (ノಥ,_」ಥ)ノ彡┻━┻ -- this method usually works.
It works, although you need to really stick to only working during the work time. I tried it when writing my thesis and miraculously I managed to work on it basically the whole day, from morning till night. Since then I've been using it sporadically when there's an important work because for it to work for me I need to lock myself up so as to not get distracted by other people.