Twenty minutes for a whole living room is crazy fast, honestly. That speed usually means corners got cut, like not using a power stretcher at all. It might feel fine now, but carpet installed that quick will almost definitely get wrinkles and loose spots in a year or two. It's less about bad luck with staples and more about how rushing the job leads to problems down the road.
Staples rarely fail on their own, it's usually poor stretching that causes problems down the line (seen it too many times). Two years without issues is possible, but those wrinkles might still be coming.