Same exist in humans also, I worked with a developer who had 15 year experience and was tech lead in a big Indian firm, We started something together, 3 months back when I checked the Tables I was shocked to see how he fucked up and messed the DB. Finally the only option left with me was to quit because i know it will break in production and if i onboarded a single customer my life would be screwed. He mixed many things with frontend and offloaded even permissions to frontend, and literally copied tables in multiple DB (We had 3 services). I still cannot believe how he worked as a tch lead for 15 years. each DB had more than 100 tables and out of that 20-25 were duplicates. He never shared code with me, but I smelled something fishy when bug fixing was never ending loop and my front end guy told me he cannot do it anymore. Only mistake I did was I trusted him and worst part is he is my cousin and the relation became sour after i confronted him and decided to quit.