My main turn-off is too much of anything (tatoos, percings, skinny, sm…)
The other one is too much editing. I love to watch porn stars changing from one position to another. Yeah sometimes it's clumsy but you can enjoy they body and the way they interact. I especialy hate when they cut from fellation to direct fucking. Intromission is often cut off but I think it's a very powerfull moment. mechanical in & out is boring next to it.