I really like Coupling, actually. And The Office is far too annoying for me to find much humor in it. It belongs in HBO's lineup of annoying sitcoms, as HBO has lately tried to refashion itself as the "Annoying Network" between shows such as the self-loathing and petty Curb Your Enthusiasm or the whining and petty Sex in the City.
But if you really want to know a sitcom I think is poor, you at least have to attempt to top Harry and the Hendersons. Look: it was directed by Scott Baio, Mr. Charles in Charge himself. How bad can you get? (And personally, I think Charles in Charge is so awful, it's actually entertaining in its awfulness... unlike Harry... was.)