And you're correct for most cases. But if you need to keep a master DB and local...

ddebernardy on Nov 26, 2015 | parent | context | favorite | on: UUIDs generally do not meet security requirements

And you're correct for most cases. But if you need to keep a master DB and local DBs on mobile devices without internet connectivity in sync, you'll be thankful to be able to generate v4 UUIDs and assume that the collision rate is nil for all practical purposes.