When you jump, you update your position maybe once per second or so as the server doesn't actually track you through the air, it just kinda "teleports" you to where you are going to land as far as it is concerned, plenty of time for an aimbot to nail your "relatively" still ****. Running on the other hand will update your position a lot more often and pose a harder target. This is all ping related tho', a low pinger aimbot will blade your *** into next week no matter how you move, and clever ones that take ping into account and can lead the target will do the same, such aimbots do exist hehe