The following in bold is from a Tribune Interview with Illinois Alum and retired Big Ten Referee, Don Capron. I'll link the interview under the bold quote from Capron. In an average Big Ten game with 150 to 200 plays, we might miss four. That includes no-calls — missed a DPI (defensive pass interference), missed a hold, ineligible downfield. A trade secret: As an official, you would much rather have one of those than have a flag that’s thrown that’s wrong. You don’t want to put a flag on the ground unless you’re 110% sure. Bill (Carollo) has a saying: I want you to love your call. If you’re not sure, don’t throw the flag.
Couple of points. When you get ordered to love your call, and millions of dollars are on the line IF the ref gets one of the four flags wrong and Michigan is out of an undefeated matchup with Ohio State and possibly a playoff berth, you can see why ALL of the calls went Michigan's way at the end of the game. It was human nature. Secondly, about the flag thrown that's wrong-this is what kills me about the Purdue Back Judge on Spoon's interception. The official was seeing things that weren't there. Ironically, the same back judge called PI on Maryland last Saturday that was questionable-at best-and who did it help? Ohio State. If Capron is right about Carollo, the back judge should not be working.