Wolves boss Gary O'Neil expects more VAR mistakes to happen this weekend.
However, O'Neil remains a supporter of the technology.
"I don't trust we will get the right conclusion this weekend all the time," said O'Neil, whose side face Aston Villa on Sunday. "There will still be mistakes, there will still be errors that we question, but I trust they are working hard to limit them.
"I have spoken to referees about some of the lines I have seen drawn on offside decisions. I was OK at maths at school and I wouldn't always put the line where they do! There are a few bits I think are off."
England coach Gareth Southgate has stated football was better before VAR's introduction.
O'Neil said: "It's getting close to there now. I've been a big advocate for VAR. I think it makes huge sense to give the guys help in something that moves as fast as the game does now.
"I am more confused about it now than I have ever been. It either needs improving or - of course this the option I don't think anyone will end up with - is that we scrap it and go back to where we were, but I would guess they will try to improve it."