one point why it is a very good movie

Rating: 9/10 (1 November 2019)

Joker is trapped in his own inability (wants to stand up comedian, but he lacks the talent / and he laughs real and spurious always in the wrong place).
Because of the bad times in Gotham and his own terrible past and present, what he had become and will become later, seems partly understandable. And that is the point:
It is the realism of this gotham world and its joker and his helpless obsessive dealing with that world that captivate you to the very last minute.