Drywall patching is the most common drywall repair we handle, and it's also the one most often done badly. Gypsum board is strong as a sheet but fragile at any cut or broken edge, so damage tends to happen in predictable ways: doorknobs through walls, furniture moved into corners, anchors and toggle bolts torn out under the weight of shelves and TVs, and square openings cut by plumbers or electricians who need access to what's behind the wall.
A lasting patch is structural, not cosmetic. The damaged board has to be cut back to solid material, the opening needs backing so the new piece can't flex or fall in, and the seams need proper tape and multiple thin coats of compound — not a single smear of spackle. In San Diego homes, the final hurdle is usually texture: many houses have knockdown, orange peel, or hand-applied finishes, and a patch that isn't matched to them shows under everyday light no matter how flat it is.
Done right, a patched hole should be impossible to find afterward — flush, stable, and finished to match the wall around it.