drrich2
Contributor
Semantics matter. Perhaps it would be useful to think of certification more in terms of an endorsement that one has training to a given standard, rather than an imposed restriction on what one is 'allowed' to do.if I ever let a certification agency tell me I have limits to my diving.
So, someone with PADI OW cert. is sort of 'endorsed' by PADI as having satisfactorily demonstrated adequate competence (I'll avoid the contentious 'mastery' term) at SCUBA diving in a range up to 60 feet deep. He might expand his competence to include responsible diving down to 130 feet over time, but absent further certification, PADI isn't willing to endorse that he's demonstrated that ability.
Similarly, a certification agency doesn't limit your diving, but places limits on the scope of what it is willing to endorse you've demonstrated competence at doing.
Insurance companies, and some dive op.s that feel beholden to their dictates, may then choose to only offer dive services to customers within the scope of what a recognized agency endorses them to do.