Old timer chewed me out for sanding bare metal wrong back in 2015
He said I was leaving too deep of scratches with 80 grit before primer. Made me redo a quarter panel on a '72 Chevelle. Took an extra 2 hours on that job but man the finish came out way flatter. Have you ever had someone older call you out on something you thought was working fine?
My buddy got called out by an old painter at a shop he worked at for using too much hardener in his clear. Guy made him strip a whole BMW 3 series trunk lid and start over. He was pissed at the time but admits now it was way less likely to crack later.
Well I'll be. I used to think the old timers were just being picky about stuff like that. But after seeing a few jobs where the clear coat went brittle and started spiderwebbing a few years down the road, I changed my tune completely. @shanegibson your buddy got a tough lesson but that trunk lid is probably still looking good today. It's the little differences in mixing that either make a paint job last or turn into a headache later.