Some things in football are objective, such as the ball crossing the goal line. We now have a way to decide definitively if this has happens. All good.
Some things are more subjective - fouls, dives etc
Some things are a mix of both. Handball requires a decision as to how natural the arm position was when the ball struck it, and whether it counts if the ball hit the upper arm or not. Offside is also a mix. A players position on the pitch is objective, but interfering with play makes it more up to the referee to decide.
For all these decisions, we've historically simply given power over to the referee & linesmen and just said 'For better or for worse, you decide, and we'll stick with your decision'. The downsides of this are manifold. Different referees will come to different opinions, and will occasionally miss the blindingly obvious, such as actual goals going in the back of the net.
There's a lot of calls on here to scrap VAR. The question I have for those people is:
If VAR is removed, will you be ok with simply accepting the referee's decision when he inevitably gets it wrong, and just accepting that mistakes from players, managers and the ref all play a part of the game?
I ask this because although I think this it's a reasonable position, I remember so many complaints from fans every week about refereeing decisions. Sometimes I question if fans know what they really want.