like Vlad The Impaler says....really tough to sustain success in the NFL without an elite offense, just much easier to maintain offense year over year than defense.
Also this is a "Disease of More" team. Pat Riley used this term and I think it applies to Seattle pretty well. All that swag and in your face bravado is great when things are going well but it does have drawbacks.
In 1988, Riley published a book entitled Showtime: Inside the Lakers' Breakthrough Season, a New York Times best seller which recapped the Lakers' successful run to the 1987 NBA Championship. One of the phrases Riley coined in the book was the "Disease of More", stating that "success is often the first step toward disaster" and that defending champions often fail the following season because every player who returns wants more playing time, more shots per game, and more money. The phrase stemmed from the Lakers' disappointing 1980–81 campaign coming off a championship the previous season.
From Lynch to Harvin to the alleged jealousy towards Wilson's endorsements. I usually hate narratives like this but I think there is probably some carryover to Sunday with it for Seattle.