Who performs every set by utilizing every muscle on every exercise. Example... today he did Chest... ( mind you he says he is working on getting muscle and lean) So I walk by him and he is benching and as he lowers the bar it OF COURSE goes all the way to the chest, makes a bounce and he pushes from there.... OF COURSE his head comes off the bench with every negative... OF COURSE the back arches making a sweet half moon shape. So .. this guy is the phlebotomist for my wife's practice and I decide to give him a bit of my advice, prefacing it with "Hey have you ever thought to try bench this way...."
I talk about if he is trying be a powerlifter then whatever.. BUT if he is trying to build muscle the portion of his bench press that is 2 inches before the bar touches and the bounce and back to two inches is virtually being wasted movement, risk of injury etc.
So he begins to tell me how "Feeling the weight " is far more important than what I called "keeping full resistance against muscle function"
Blood begins to drip from my ears and nose.. and I wanna squish him.
This is the same guy who does lat pulldowns and as he reaches the full negative allows his ass to raise 4 inches off the seat and slugs the weight back down, no pause at contraction.. rinse repeat.

He puts 230 on lat pulldown and cheats for 8. I put 260 on and do pause reps for 12 and he just doesn't get it.. These are the people who new people see and mimic and end up fucked for life.