That's part of it. A good coach knows what he wants in a quarterback. Stoops got to town, hired an offense and went out to find a quarterback. If it hadn't been Heupel, he would have gotten someone else. Listen, they're not that easy to find.
Good quarterbacks are rare.
America is full of guys who can throw and run a football. Good quarterbacks are everywhere. Good coaches, too. Just because OU couldn't find either one doesn't mean they're in short supply. Kansas State can't find anyone to replace Michael Bishop.