The Big10 has 12-0 Iowa playing 11-1 in a conference championship game. A conference championship game Oklahoma won't have and risk losing in.

If the Big10's 12-0 Iowa finally loses a game that happens to be the CCG they will be left out of the CFP. A conference championship game that Oklahoma doesn't have.

If Oklahoma and Iowa end up both 11-1 then Iowa will be left out because their loss was more recent than Oklahoma's all thanks in part to Iowa playing a CCG that Oklahoma and the Big12 avoid.

If Iowa loses in a close game to Michigan State you could say their loss was better than Oklahoma's to dumpster fire Texas.

The Big10 has the most weight in college football and they will be coming after the Big12 for not having CCG.