All of mine are in rotation.
I go to my spreadsheet and see what jumps out at me. Maybe a name I havent used in a couple years. Maybe it was 3 years since I shaved with it. Or maybe I just want to use something I made scales for or Ivory.

One of the 325 razors will be picked, stropped and shaved with. I normally will look at what I finished the razor on after the shave. And i always mark how the shave went and change the date on the spreadsheet.

Some days its been as long as 4 years between shaves with a razor but its still in rotation.