1. Really terrible CGI. The Hulk just looks plain fake. And he is bright green. Like lime jell-o green. For some reason, when he gets shot his body jiggles like jell-o. Whoever did the CGI never studied anatomy and apparently never watched another human being move, because you should see the weird contortions of the Hulk's muscles when he jumps.
2. Terrible plot. There's this creepy janitor and he turns out to be Bruce's dad who experimented on his own baby boy because he's one sick puppy who was more concerned about science than his son. Bruce, as the Hulk, has to fight his dad's hunting dogs who have been turned into Hulkdogs. Eventually his dad becomes a version of the Absorbing Man. Their fight scene is mostly talking and makes no sense. After the movie was over in theatres, I talked to several people. None of them understood that scene.
3. The presentation of the film was awful. The scenes transitioned with PowerPoint slide effects. No. Seriously. At one point there is a bunch of boxing in and out and multiple scenes being presented at the same time with most of the screen being black and unused. Looks like a kid got ahold of the editing equipment and went wild.
At least the MCU version was better.