I worked with a guy who fits this description. If there’s something he can reinvent poorly, he’d do it. A big part of what I did while working on the same team as him was slowly chipping away at his weird domain by introducing standard tools. I always had to advocate for them in such a way that they were solving a different problem, and then slowly work towards a point where some of his homegrown stuff became unnecessary.
As to the job security idea: the only people who do this are people who aren’t good at creating real value, so they have to try to create niches where they’re needed.
As to the job security idea: the only people who do this are people who aren’t good at creating real value, so they have to try to create niches where they’re needed.