There's an old quote by Fielding Yost that goes, essentially, football games are never won, they're only lost. I assume because the internet tells me so that Yost actually said that at some point...but it does reek of that "fortune cookie wisdom" that probably wasn't such a thing some 100 years ago. But for a sport that was still in it's infancy in Yost's era, such a poignant observation could've easily been made.
But there is some legitimacy to the notion that football outcomes, especially at the amateur level, are often the result of miscues rather than overwhelming dominance of sound, mistake-free football.