To be fair, one bounced off a facemask, the last when his protection broke down and the defender hit his arm. But the others, most certainly.
The first one should have been caught, plain and simple, not on Lee at all. Second one, either Lee threw it to the wrong spot or Stanley Morgan turned the wrong direction, not sure whose fault there. Third one wasn't as bad as some made it out to be. They showed the replay from behind Tanner Lee, and you can see from that view, while the guy he threw it to was covered, he appeared to have a step that the ball could be fit into. The Oregon defender simply made an excellent cut across the receiver and intercepted the ball. Not a great throw to make, no; but it's not like he threw it to someone who was draped in coverage with no chance to catch it. Final one, hit as he threw, not his fault.
I already made this comment once, but I'll make it again. On at least some of his passes that missed the mark; you need to go back and watch the play again before just saying he flat out missed. One comes to mind was when Tyler Hoppes was open, and Lee's throw was a little high, and it went incomplete. First of all, while the throw was slightly high, he was still able to get his hands on it and should have been able to catch it. Second, watch the replay they showed on TV. You can clearly see as the ball travels through the air, an Oregon defender jump and JUST miss tipping the ball, his fingertips are within inches of the ball. He threw the ball high to get it over the defender, yet still managed to make it catchable, albeit a little high. That was a good throw, not a bad one.
Later, either the same drive or the next one, can't remember for sure; there was a third down pass to Conner Ketter I believe, where Lee appeared to just miss him a little wide, like he threw the ball a little too far ahead. First of all, again the pass was within range that it could have been caught, requiring a possible dive or just reaching, but still catchable. Second of all, again; you have to go back and watch the replay. On the replay, with a shot from behind Lee again, you can see why his throw was a little wide. Basically smack dab in the middle of his throwing lane, the lane to get a perfect strike to Ketter, stood a ref. If Lee would have thrown the perfect pass, straight to Ketter, it would have almost certainly hit the ref and either fell harmlessly to the turf, or taken some crazy bounce and gotten intercepted.
I'm not certain about all of his incomplete passes, but he certainly had a few drops; and some of his "off target" throws only appeared that way because something between him and his target was missed.