In particular, so many technical leaders work in a vacuum with no context. People joining a company as a technical leader needs to absolutely dig in and understand the existing landscape and processes, and not try to just blindly reuse what they did at the last gig.
In some cases, you were only hired because the previous person "was doing a bad job" and they need someone "to do a good job" but in reality, the previous person wasn't even able to make any decisions, and was in fact just being strung along with the top-down direction, leading to bad results, and that person got fed up and left.