Pete, on KIRO, said he knew he shouldn't challenge, but someone on the headset said the ball came out and he, in all the excitement of the game, noticed the clock was at about 6 seconds, so he just quickly got the refs attention and challenged the play. He said he realized what he did after he threw the flag but it was too late.
Little things like this really need to be rare occurrences, and on their own, the occasional error like this isn't a big deal, and I don't think it's necessarily a sign of a bad coach, but I really am starting to wonder if Pete's up to running an NFL offense.