Bill Belichick’s Patriots are the only team to exist outside of these rules. Their middle rounds were littered with guys who did nothing, or next to nothing, in the NFL. Their draft success ranked in the bottom third of the league during these seasons. But even in 2009, those guys made up a large chunk of the roster. Nearly a third of the roster was made up of guys who were never drafted at all; the Patriots signed them for cheap and plugged them right in.
NFL daft: A partial history of draft day’s terrible decisions and total failures – SBNation.com
H/T to Rich Hill for the find.