I took my steering head apart a couple years ago to repack the bearings. I found that the steering stem nut, which was supposed to be tightened to 94 ft/lbs, was only finger tight. That's the way it came from the dealer, because that was the first time I did any maintenance on the steering head bearings. There's no way I would believe that the steering stem nut came loose on its own if it had been tightened to the correct torque setting, so someone either in the factory or the dealership tightened it incorrectly. If they didn't tighten that properly then it's not a stretch to believe someone in the assembly chain didn't tighten someone's steering head bearing locking rings properly. Especially when you have to use a special crowfoot torque wrench extension to do it, and the torque wrench has to be at a 90 degree angle to the crowfoot wrench to set the proper torque that's described in the manual. It also has to be done in the right sequence, where the lower locking ring has to be torqued to 38 ft/lbs (presumably to seat the bearings in the races), then loosened completely and retorqued to 13 ft/lbs. If a tech wasn't reading the manual correctly and only saw the "13 ft/lbs" setting, you can believe that the steering head would not be torqued correctly and would probably be very loose.
No one is infallible, and even a highly trained tech can screw up. NASA employs some pretty highly skilled subcontractors, but you still have things like the Challenger disaster and Apollo 13. If I experienced the issue that the OP did, in spite of knowing that my bike was brand new and assembled by a top notch manufacturing giant, I'd still suspect right off the bat that either the headset was loose or I had a defect in a tire. I wouldn't ignore what the symptoms pointed to, regardless of the perceived unlikeliness that the bearings had been improperly adjusted.