I've only seen that once in my career. One developer rewriting existing code constantly, to such an extreme degree it's unfathomable.
He rewrote large amount of scripts (often overnight). Other developers would wake up the next day or continue the project next week, only to find a swath of issue reported by users and the project is gone (rewritten and moved). Did that for while, destroying the work of many people across a number of teams, making enemies and leaving a trail of projects ablaze. Didn't manage to get him fired (organizations rarely fire people) so over time other developers simply stopped working (what's the point when it will be undone the next day) or left.
At first, I thought this was the normal junior mistake. Reading code is quite hard, so one reflex of junior developers is rewrite existing code to make it "prettier" or "better", of course it's just a path to understanding the code because they understand what they just rewrote after the fact. One aspect of learning real world software developer is to stop the urge of constantly rewriting like that.
But that was not it for this developer, he went on and on never learning. Trying to mentor lead nowhere, his stubbornness and deeply ingrained vision was stronger than the will of any lead or manager. Worst challenges were, he fundamentally disagreed on almost all objectives, required features and design decisions, he simply had a different vision and ideals deep down that there is nothing you can do to reason about. He was ultimately unmentorable and unmanageable.