When you run in a survival world, you don't immediately sprint. It's only after you stop that your FOV increases and the sprint particles show below your feet. When you walk after doing this, you walk in the same speed as sprinting. This happens minutes upon "joining" your Minecraft world.

This also happens for scaffolding. Holding the jump button doesn't lift you up but instead the game registers it as a normal jump. Only when you've done this a second time that you start to rise up the scaffolding, but you don't stop even after the last scaffolding on top has been reached. You keep floating and floating even tho there's no scaffolding below you (assuming you still hold the jump button).

You also can't hit mobs exactly where they are, as usually they're four to five blocks away from their bodies. In the same way, I usually get damaged without warning despite no other threats around me, but I would always see a zombie attacking or a skeleton shooting at a random place where I had been a few second ago. When I rush forward to kill, I can't kill because the zombie's hitbox isn't in the original body of the zombie.

Sometimes I'd die randomly or take intense damage ten minutes after actually "supposedly" taking damage. Just when I think I survived a fall from lava and getting away from it, I return back to my base (and walk around, do a few projects im working on) and suddenly I get reduced to half a heart.