Taking a prototype to a real product is where AI app builders stop looking similar. Cursor and Mocha can both help produce an impressive first draft, but they diverge hard once the job becomes ongoing ownership: changing logic safely, debugging regressions, moving environments, and keeping the app alive after the initial prompt glow fades.
That makes this a useful stress test because the failure modes are not cosmetic. The product either becomes code you can inspect, run, and maintain, or it remains a generated artifact whose behavior depends on a hosted layer, weak export paths, or repeated AI fixes every time something breaks.