A door built around 1982, which is the typical build year for this part of Rialto, has had four decades of heat cycling on its panels. The region sits in a moderate heat climate band, and steel panels that age expand and contract through the day, which loosens the rivets holding panel to panel and warps thin-gauge sections over time, especially the bottom panel that takes the brunt of sun and the occasional bump from a car bumper. Houses built in this window, 1958 through 2003 across the broader area with a median around 1983, almost always went up with a single steel skin and no insulation layer, so the panels flex more than anything built after codes required a foam core. We see the same failure pattern across that housing stock: hairline cracks along the embossed wood-grain pattern, rust starting at the bottom seam, and hinges that have worn their mounting holes oval from decades of panel flex. None of that is a Rialto-specific defect - it's what that era of door does anywhere it's installed - but it does mean a huge share of the doors we're called out to here are original equipment, not a replacement someone put in ten years ago.