Last season "Let's Ride" became the meme motto of the NFL. The Broncos incessant need to repeat it endlessly as part of Russell Wilson joining the team became a punchline when everything went to hell.
There was a way to come up with something that kept expectations measured for the upcoming season without it being sad as hell - but Denver made it pathetic.
There has never been a worse sports phrase. These are branded shirts too - so it's not like Ben Powers came up with this idea himself. It's not even a call to action with a deeper meaning like "Be Uncommon." That would still be really dumb, but better than just "UNCOMMON."
When the explanation for your weird phrase is that winning in the NFL is uncommon, then you have problems. Firstly, winning games isn't uncommon. You have a 50 percent chance on 17 attempts. If you just rolled the dice you'd win 8-9 games. More than that, it's immediately telling everyone "we know we're going to suck, but we told y'all that winning is uncommon." The very best you can hope for is that you defy expectations and have a good season, but then you've only told people "we were uncommon," and that's sad.
The NFL is full of terrible slogans, but "UNCOMMON" is the worst.