When the teacher fails to teach you

Guy in my lab would never read the lab procedure and would talk shit about the instructor cause if his own inability to follow written instructions, he'd also talk shit about me cause I'd try and lead everyone since the others were just as clueless and I'd ignore him at least untill the last day cause I didn't give a fuck about playing nice anymore so I put him in his place and he shut the fuck up for the rest of the day and we got through our lab a lot more smoothly than usual