I watched a very well-written piece of software written by a group of brilliant people turn into a pile of bugs by basically the same brilliant people and all t

I watched a very well-written piece of software written by a group of brilliant people turn into a pile of bugs by basically the same brilliant people and all this was caused by mismanagement. Many bad decisions by many powerful were made, but a lot of credit needs to be given to one particular poisonous manager who actually managed to corrupt the entire organization into the mess that it is today. He even managed to split the developers into two groups of "us" vs "them". Things got so bad a whole new entire organization was formed to write new software to replace the old one. Recently this poisonous manager was moved to be part of the team developing the new thing.