[Arnt]

Only as a matter of low level storage. It won't trigger ON DELETE CASCADE and that kind of thing.

This is a kind of misunderstanding I've heard from others who were first exposed to hacky things like early mysql. Databases are something else. A different kind of beast. If you use a database, and Postgres is the best of the DBMSes, then you can say things like "a lead shouldn't be deleted before three months have passed, no matter what" or "a lead can't be deleted until its state column says it's been handled" and the DBMS will make sure of it. If you have a bug that would involve leads being deleted prematurely, the DBMS will reject your change. Your change just won't break the database.