Because everyone expected Gonzaga to be really good, so when they are really good Few gets no "extra" credit. It's the same reason that a guy like Chuck Noll never won the NFL coach of the year. His teams got good, and so when they were good everyone expected it so he didn't get any credit.
That's an award that writers like to vote for a guy whose team ended up better than the writers thought they were going to be when the season started. Michigan was better than the writers thought they would be, so that must mean that Howard did a great job (and I'm not suggesting that he didn't do a good job) because there was no way that the writers could have been wrong in the first place.