What makes ANY caliber become popular?

As an "in-between" caliber goes, what about the .41 Rem Mag?
More power than the .357 Mag, yet less recoil and easier to handle than the .44 Rem Mag.
I have a S&W M57 w/8 3/8" bbl. It's built on the N frame.
The only difference between it and a M29 is that a little less metal was removed during production. The M57 is just a touch heavier. With a bit milder cartridge, recoil is more manageable.
I find the .41 Rem Mag to be a perfect 👌 compromise.
Initially, LEO's loved it, but as the wheel gun gave way to the semi auto in law enforcement, the .41 Rem Mag has pretty much died.

There are hundreds, if not thousands, of perfectly good cartridges that are languishing just because of "popularity"!
Who knew?