Not only can churn be disastrous as you mentioned, but there are situations where it can never even have a shot to succeed. It can start out on the wrong foot so easily bc programs all think they are worthy of getting a Nick Saban/Urban Meyer-level guy.
Then reality hits.
Then they don't give the new person (that was like the program's fifth choice and probably the fans' 100th choice) enough time or support to get back to being able to win at a high level.
Wash. Rinse. Repeat.
None of the above is a commentary on Dino, btw. I'm just saying, in general.
Getting a program to the level where it's consistently winning at a high level is very hard. It takes a lot of support, especially financially, the right coach and staff, the right AD and still you need to get a bit lucky.
Honestly, I wish I appreciated the P years more than I did. I used to think winning only 6 games was a travesty and if we won less than that the world would just explode.