A lot of the specific details of exactly what transpired between Edward Norton and Marvel on the set of the second Marvel Cinematic Universe film, The Incredible Hulk, are not entirely clear.
The fact that Edward Norton wanted a better script is certainly known because the actor actually did some rewrites to the original script himself.
However, what can be said is that things didn’t work out.
There were then also reportedly some disputes on the editing side as chunks of the movie that were filmed never made it into the final cut, and there were different opinions between Norton and others regarding how long the film should be.