What was his basis for rejection? I'd like to imagine he considered the work complete at that point and was rejecting milking the life out of the characters and

What was his basis for rejection? I'd like to imagine he considered the work complete at that point and was rejecting milking the life out of the characters and world. In the unending wash of remakes and unnecessary decade+-later sequels today I sometimes wonder if original creators were facing some monetary hardship and gave in.