Or, and I'm speaking from my experience in TF2 here... they're just good.
TF2 is an interesting case study because it's a very old game with a very high skill ceiling. I have 2,000 hours now. Players with 4,000 hand my ass to me.
The difference between an aimbot and a sweaty 4,000 hour sniper is close to none. You peak the corner and within 200ms you're dead. It's easy to think they're cheating, then you open up their steam profile and no, they just have even less of a life than me.
They'll even headshot you when you got invisible on spy. Yes, really. They have so much experience their hands have remembered the movement speed and trajectory of spy. So you go invis, and then they can predict where you're going to be and headshot you. Especially so if you go for a health pack or ammo. It's really crazy stuff, but not cheating.
I used to play with a notorious TF1 sniper who constantly got cheating accusations. Saw them play live once, and they were just that good. But with a catch - they lowered screen resolution to the absolute minimum, meaning higher refresh rates, and bigger pixels. Bigger pixels meant easier head shots, as if a bullet path hit a bounding box, the rendered pixels of the target were then used to determine hit/miss and hit location. They also adjusted their screen contrast making everything look awful, but apparently easier to make out the important details.
TF2 is an interesting case study because it's a very old game with a very high skill ceiling. I have 2,000 hours now. Players with 4,000 hand my ass to me.
The difference between an aimbot and a sweaty 4,000 hour sniper is close to none. You peak the corner and within 200ms you're dead. It's easy to think they're cheating, then you open up their steam profile and no, they just have even less of a life than me.
They'll even headshot you when you got invisible on spy. Yes, really. They have so much experience their hands have remembered the movement speed and trajectory of spy. So you go invis, and then they can predict where you're going to be and headshot you. Especially so if you go for a health pack or ammo. It's really crazy stuff, but not cheating.