This area sits in a moderate-heat climate band, and steel panels take that heat differently depending on orientation. On a 2012-built house, the door is usually still its original steel sectional, and the panels facing south or west spend years absorbing direct sun. Foam-injected cores expand and contract with that heat cycle, and eventually the steel skin bows slightly away from the foam - you'll see it as a faint ripple across one or two panels, usually the top ones closest to the sun. That's not a manufacturing defect ten years in; it's just what foam-core steel does under sustained heat exposure in this part of Texas. The other common failure on doors this age is at the bottom panel, where lawn equipment, a bike pedal, or a car bumper clips the edge - simple impact damage, not weather-related, and usually the easiest panel to replace since it's the one section made to take that kind of hit. Either way, because the stock here is fairly young and fairly uniform, we're rarely chasing a panel style nobody makes anymore, which isn't true everywhere we drive to.