Great teams become great because they understand the logic of high challenge. It stands to reason that people will rise to the mark set for them. It is true that not all people will. If both of those statements are correct, then it is logical to set the bar high. If the expectations are set low, then low is the highest the best people will achieve. If the bar is set high the best people will achieve more and the ordinary people will achieve exactly what they would have achieved if they were never challenged. Nothing is really risked and the best people are given an opportunity to stand out. Greatness requires the opportunity of high challenge.