Not counting antiques and guns that were simply worn out, the worst pistol I own (or ever owned) is a Rogak. It is a licensed copy of the Steyr GB, which was not one of Steyr's better ideas, but the Rogak is total junk. It is so poorly made that the gas leakage keeps it from functioning when fired. That really doesn't matter, since the hammer spring is so weak the gun won't fire 90% of the time, so it only fails to feed 10% of the time.
When it came out some of the gunzines praised it to high heaven (though Soldier of Fortune was honest enough to say it was a "boat anchor").