Then the whole locking thing doesn't really cause any revenue to the carrier... unless you do this to force people to use your carrier for X years and calculate

Then the whole locking thing doesn't really cause any revenue to the carrier... unless you do this to force people to use your carrier for X years and calculate revenue based on that. In any case, at least here in Switzerland, carrier-locked phones aren't a thing anymore - I guess they realized it's just stupid and impractical.