I can't remember what coach our commenter said it, but it went something like this, "Nebraska struggles to win games, because Nebraska expects to win games."
That is paraphrased, but I think there is truth to it. The schools you mentioned (KSU, Iowa State, Iowa, etc) know that winning requires a whole lot of effort. And for players to give that effort, they need to know that they need to work longer, harder, faster than the other teams if they want to win. I think NU is a great job for any coach, but I also think because it is such a great job that players feel entitled and that winning just depends on who the coach is and whatever effort the players give should be "good enough".
Does that make sense?
I feel like I'm rambling...
Frost tells fans, and his players, that "the talent is there, we just need to execute"
Pelini said it too.
Callahan said it...
Riley probably made a comment like that also.
That doesn't make players hungry. It allows the players to make excuses. IMO.