He was just ahead of Verstappen and wanted to stay there. The current cars make overtaking pretty difficult in most circumstances due to the ridiculous aerodynamics.
Also, if Verstappen is ahead he is a very tricky customer to get past. He has a habit of doing that Schumacher thing of turning in on people passing him, and giving them the choice of backing off or crashing.
Hamilton gave him a little taste of his own medicine yesterday I suppose. Although Hamilton was far enough ahead to turn left without causing Verstappen a serious problem. All he had to do was go over the kerbs and rejoin the track still behind him.
He chose not to do this though and aimed his car into a gap which by that point was about two feet wide.
There was only one possible outcome and he well knew it.
As Toto Wollf said, it was what they call in football, a tactical foul. Similar to hacking down down a player who is about to score a goal.
I think the kid has psychological problems, due to his family background, is dangerous and if someone doesnt sort him out, he,s going to hurt someone.
No denying his talent, but his arrogance is intolerable.
Even Mr. Spice Boy struggled to put up any meaningful defence of him yesterday.