Sylvester McCoy didn't just wear the most question marks of any Doctor — he also played the role the longest. A British game show incorrectly claimed that David Tennant played the role for longer than McCoy, leading to a recount.
According to the Daily Mail, the game show Million Pound Drop asked contestants which actor had played the Doctor for longest: McCoy, Tennant, Paul McGann, or Christopher Eccleston:
A husband and wife team, Johnny and Dee, decided to split their £650,000 between McCoy and McGann, but the host told them they were wrong — David Tennant played the Doctor for longer than either of those two. The two were disqualified and lost all their money — but afterwards, fans called the program to complain. McCoy played the role from 1987 to 1989, and then reprised the role in 1996 — making him technically the longest-serving Doctor. McGann, meanwhile, was the Doctor from 1996 to 2005, if you count all the audio plays he recorded during the time the show was off the air. (And the question says nothing about playing the Doctor on television, just playing the Doctor.) Tennant, meanwhile, only played the Doctor from 2005 to early 2010.
So actually I think Johnny and Dee should have gotten to keep all £650,000, since McCoy and McGann played the role for about nine years each. The duo returns to the program, with their money reinstated, this weekend. [Daily Mail]