They sure as hell did, all the time. Shit, Vladimir Komarov, a Russian cosmonaut in 1967, crashed full-force into the Earth after dying from re-entry heat, despite scientists saying THAT EXACT THING WOULD HAPPEN, because the capsule was little better than sheet metal bolted together and the parachutes literally did not work. The people who were supposed to check the work at the factory didn’t know better - they knew it had been constructed, and that was that. Brezhnev wanted it done, and wanted it done before the anniversary of the Revolution. So it flew, and a man died because it flew.