The other reasons surely involve Wilson, who caught nine passes for 100 yards Saturday but still seems to be trying to satisfy Leach's demands for reliability and physicality.
The Cougars (2-6, 0-5), who will try to break a five-game losing streak Saturday at Utah (noon PDT, Pac-12 Networks), submitted their most complete, most physical and overall best performance of the season at Stanford, Leach said.
But the first-year Wazzu coach is still looking for consistency from his receivers, and most notably from Wilson, the school's all-time leader in career reception yardage.
The quest took another setback when a miscommunication between Wilson and quarterback Jeff Tuel undermined the Cougars' final stab at a game-tying touchdown from the Stanford 19-yard line, resulting in a sack as the final seconds elapsed.
"He was supposed to run a comeback and he kept running downfield," Leach said of Wilson. "If they're not on the same page, it's not going to do anybody any good."
That echoed a postgame interview in which Leach said Williams outplayed the star junior in practice last week and early in the Stanford game before Wilson "got hot toward the end. If Marquess wants to play the whole time, he's going to have to quit being hot and cold."