The blurb for Bill Belichick Offseason Simulator claims:
Any fun you may have, or amusement you may find, while piloting this simulator is purely accidental, and should be reported as a software bug.
If that is to be taken seriously, then I am sorry to report to the author that this work is riddled with bugs.
It seems certain, however, that this tongue-in-cheek warning is not to be taken seriously. BBOS is a short-form absurdist comedy that can't even take itself seriously as a lampooning of Bill Belichick, who at the time was head coach of the New England Patriots. "Serious" is not a word that applies to this endeavor.
I know nothing about the Patriots or Mr. Belichick's career as a football coach. Author Jon Bois is a sports writer of some note about whose career and work I'm similarly ignorant. Knowledge of these things is almost completely unrelated to enjoying this game, which draws the bulk of its tropes from text adventures, adventure games, RPGs and popular fiction, all of which are blended together in a base of pure author id.
There is a slight unifying framework to this game that involves collecting cards in order to design the perfect offensive play. It's pretty incidental to the play experience, which is more about having fun with a series of pixel-animated vignettes featuring everything from an encounter with a "roving rock music gang" to a visit to a hardware megastore to being summoned to another dimension by a wizard to interrogating an NFL player about favorite music and recipes.
BBOS is a great choice for a lunchtime or commute "snack" game (though you may need to make use of its bookmark feature to complete it across more than one session), or as light entertainment for a rainy afternoon. If you're on the fence about this one, give it a shot -- if the first five minutes amuse you, you can expect to enjoy the rest.