He wasted an entire year. That's pretty disastrous. He had the opportunity to earn the starting QB job right off the bat, and when he squandered that, things started to go downhill.
Even when Hoyer was playing well to start the year, Johnny knew that he was one play away from being thrust into the starting role, but he didn't care. He didn't put in the effort. This had been alluded to during the press conferences, without downright pointing the finger and saying "He's just not giving us his all."
As Hoyer's performances got worse, fans and media began demanding that Johnny get a chance. The coaching staff still stood behind Hoyer. On the surface it seemed like they were doing as a way to reward Hoyer for getting them as far as he did, but I think we can all agree that it's more likely that it's because the coaching staff knew that Johnny wasn't ready and wasn't really trying to be ready.
When Johnny finally came in for a drive in the Bills game, Browns fans were thrilled by his amazing performance! He came in and marched the team right down the field to score! Wow! Except that the Browns were already losing that game and the Bills were playing a prevent scheme. The very next drive Johnny got knocked to his ass and lost a fumble in the endzone (which was called back, but it was a bogus call). Still, it provided a glimmer of hope.
The next game that all went away. Facing a team that was prepared to play against him, he accomplished nothing. He played a downright terrible game of football against a team that we decimated earlier in the year. And then he scrambled on a play and got injured, the end.
Is it disastrous? I'd say it's pretty close. We went out on a limb and drafted him when everybody was passing on him, and it looks like we probably made the wrong call. Hopefully he can work out his demons in rehab, but I don't want him on our team. When your father comes out before the draft and says that you're too immature to play in the NFL, that's pretty bad. You'd think it would have been a huge red flag to teams. But the organization fell into the hype. And we wasted a year training a quarterback who would rather be out partying than helping his team win a football game.