Is it really bad to rewrite a script?

Generally script re-writes aren't too bad a thing, especially if the initial draft was weak. From what I've heard of Godzilla, it's been given about as many drafts as most blockbusters these days. It's status quo to have a film's script re-written a few times.

The problems come when too many writers re-write the script. It leaves the idea that perhaps there are too many cooks in the kitchen and the script will become messier and less focuesed with each new writer. Godzilla's had around five different writers take a stab at it.

Not all will recieve credit and that largely depends on what was re-written. I can understand why some people might be worried about that. From what I can tell though, the changes made by a couple of those writers were very minimal. I'm not too concerned about it.

As an aspiring screenwriter I can tell you rewrites are essencial. Ive had agents point out in scripts I've loved and read a thousand times over plot holes I had completely missed. Everybody comes together to make a film better. Sometimes integrity is shattered and too many producers/actors want the script changed to suit them more or to reach a bigger audience but for certain a first draft making final cut is EXTREMELY RARE.