As a manager I'm 100% convinced that culture drives performance and that the manager that wants to run the most efficient business or department works on the culture first. Communication, direction of focus, teamwork etc. all have to be addressed early. The interesting part is that being hired during challenging times, like Covid as mentioned above, is an opportunity to make those important changes quicker. I worked in Iraq during the war and found that the fast turn over was often my friend when setting up at a new base. Employees that had followed incentive patterns set up by predecessor that encourage venal, self-serving, uncommunicative, uncooperative actions were numerous. After all, the previous managers knew they weren't going to be there long either. Yet, the remolding of culture was always, and is always, an uphill battle. Once you're rewarded for poor behavior, it's hard to trust that the 'new way' isn't just a trap. I remember one employee referring to the new way as "setting me up for the okey dokey", as if I spent enormous time and effort wanting to hurt her, not build a better culture. It's sad but true that turnover is sometimes your friend for the truly resistant. That said, it was always worth the struggle. Within a year, people would apply in droves to get into my departments.