All NFL players—from running backs and wide receivers to long snappers and kickers—are subjected to criticism at one time or another. But no one, and we do mean no one, faces the amount of criticism that quarterbacks face on a week-in, week-out basis. Even when QBs are playing well and winning games, they're still forced to deal with critics who think they should be playing better and winning games more decisively. It comes with the territory when you line up under center for an NFL team.

Some quarterbacks get it worse than others, though. For example, Donovan McNabb—who turns 38 today—once said, "Nobody has been criticized as much as I have," during a 2012 appearance on ESPN First Take. And while we don't necessarily agree with his assessment of him being the most criticized QB ever, he certainly faced his fair share of criticism during his days with the Eagles—from getting booed by Philadelphia fans during the 1998 NFL Draft to having his heart questioned following Philly's loss to the Patriots in Super Bowl XXXIX.

So to help "celebrate" McNabb's born day, we put together a list of The 25 Most Criticized Quarterbacks in NFL History. Playing QB in the NFL clearly isn't always all that it's cracked up to be.