VAR

Taking six minutes to decide is pointless. VAR could work if they had a rule that says if it is so borderline/unclear that VAR cannot assist within 30 seconds/3 replays or the panel is undecided, then the original ref decision stands and the game continues.
 
The ref still decides after looking at the TV. So that all adds to the delay.

It has to be a one stage process, and only for game changing decisions like a sending off or a penalty awarded. In the US they have the video played down to the referee on the sideline so they can see the evidence quickly.