FWIW, the round is good enough for whole police departments to adopt it. They make the statement that 357 Sig gives them the penetration that the 40 S&W doesn't, ie., car doors, some armored vests, building structure etc. And they still don't have to deal with the recoil of rounds like the 10MM(which I have never had a problem with).
It was marketed to law enforcement it never gained the popularity of the 9mm and .40S&W.
Ammo cost more than 9mm and .40 S&W
Ammo isn't as readily available as 9mm and .40 S&W
Bottleneck case is a bit more complicated to reload than 9mm and .40 S&W.
Doesn't feed as well as 9mm & .40 S&W.
This is just a few reasons. There's plenty more.