The one time mine failed was when I was using it on a friend's flat! Luckily, I carry 3 cartridges (maybe overkill?) That was a non-threaded cartridge. May have been a fluke (likely from what others have said), but now I use threaded cartridges. The inflator is a Genuine Innovations Ultraflate Plus, so don't think it was the inflators fault, leaving only user error or the cartridge. Luckily, it doesn't see much use, so the extra $ for threaded cartridges isn't a biggie.