Same with kneeling on someone's neck. Maybe the officer intended to deliberately seriously injure or kill the man.
I genuinely think it is more likely that he was too stupid to realise that kneeling on someone's neck will kill them, believed the bystanders to be idiots and thought he knew best because his training is crap.
He didn't know how to subdue a man resisting arrest, couldn't de-escalate the situation, unable to do anything but shout instructions and use force.
I genuinely believe the US would be better to hire robots at officers. All your law requires is for the officer to point a gun and shout 'comply'. Any donkey could do that job.
Unfortunately that's not how the real world works and officers have to deal with people who don't understand instructions, maybe don't speak English, are mentally incapacitated, drunk, high on drugs, shocked/injured, roided up, having emotional break downs etc etc.
So unless the suspect is another officer at police academy who follows instructions to the letter, moves at a speed which the officer trained for, uses hand movements exactly as he prepared for... the suspect is probably getting shot or injured.