Cameron Herold says new COOs should spend their first 30 days observing every meeting, call, and email without making changes. Take notes on what's broken. By day 30 you'll have roughly 60 improvement ideas to stress-test before you touch anything.
Chapters
In the first 30 days the second in command should show up with a notebook and a pen and they should walk around the company for 30 days sitting in on every meeting in person or virtual meeting with every direct report meeting with all the other directors and VPs listening in on sales calls, listening in on customer service calls, getting blind cc'd on as many emails as possible, reading up on the sops and processes in the company really watching and observing and making notes of all the stuff they want to change. Fire Bob, integrate this tie in that bring in this software but don't do any of it. Just make notes of all the things and maybe at the end of the 30 days you've got 60 things you want to do. In month two you go back and revisit all of those 60 things and you stress test them all, you know asking some questions like and you learn oh Bob really isn't as bad as I thought he was.