What is your approach to filling gaps in critical roles such as managers, COO, or CEOs from an acquired company?

When a new company is acquired, do you, as the owner or managing partner, run it yourself, or do you bring someone aboard from your network to run and manage the daily operations? I understand each situation is different but is there a go-to method that has worked for you? For example, I acquired a small industrial distributor several years ago with a 20-year history and declining sales but high experts, but this seemed to make things worse. I believe it’s essential to have some approach heading into a new acquisition that margins. I left the current staff to run the day-to-day for the first year before I made changes to key personnel. In hindsight, I should have intervened sooner and brought in key staff or ran the company myself. I brought in several consultants and industry addresses these challenges. In closing, I would love to hear about your experience or process and how you and your acquisition team approach managing a new company, especially if there is no or little leadership.