What happens when the person who knows something isn't around? (18+)

I'm researching a problem around lost team context, decisions, project history, unfinished work, etc. that effectively disappear when someone leaves or is unavailable.

Curious how other teams handle this today. I put together a short anonymous survey (~3 min) to collect some data:

https://forms.gle/TKBoD4guTRy2XvZ96

I'm trying to validate the problem before building a solution. Honest/negative answers are especially useful.