Tiny tweaks in a story can cause a tidal wave of changes.
Maybe I’m a writing freak, but I actually love revisions. A single change can impact a novel on multiple levels, which is both cool, and terrifying.
Tweak a character’s backstory or change the rules of your world’s magic, and bam! Your entire novel starts to shift under your feet. One change leads to another, and another, and then you realize the larger ramifications of all those changes and before you know it, it’s practically a new book.
Which isn’t necessarily a bad thing, but you want to make sure it’s what you want.