@HeavyDuty
That is where I am as well: even if the sidearm never changes a person can need multiple holsters, depending on what he's been doing recently.
Examples: a shoulder may go out and until it recovers full range of motion, which on occasion may take a year or more, drawing from behind the hip is a non-starter. Hernias or scar tissue (as you noted) may restrict AIWB. Even if the manner of carry remains the same, infirmities may require the gun to be changed to the other hip.
And the offside holster facilitates defense with the "weak" hand. That, by itself, is reason enough to at least consider having a holster to use when the "strong" side shoulder is out for maintenance.
A reasonable argument can be made that one gun may require four holsters: an AIWB and an OWB on both right and left sides.
Duces