I don't know but I've read articles where he says that it is because he's from Tacoma and that usually everyone focuses on the players from Seattle instead.
I understand that's his words, but plenty of talent comes from the Puget Sound area south of Seattle. Just off the top of my head some current or fairly recent NBA guys include Isaiah Thomas (Tacoma), Marvin Williams (Bremerton), Rodney Stuckey (Kent) and Michael Dickerson (Federal Way). I'm sure you guys remember Donny Marshall fondly, another Federal Way product.
Just out of curiosity I looked at results for State Playoffs in Washington for the last 20 years or so. 4A and 3A are the two highest classifications, they're virtually interchangeable in terms of talent level. There have been quite a few State Champs or runner ups from Tacoma, Kent and Federal Way during that time frame.