It's counter to human instinct to watch a train wreck approach and people siting idly by doing absolutely nothing.  Yet, this is precisely what Hashem does when the nation requests spies to assess the Promised Land.  God foresees the impending disaster but allows the mission to proceed nonetheless (see Rashi).  The result is devastating - the entire generation perishes in the wilderness with only their children being allowed to enter 40 years later.  Why would an Omniscient God set the nation up for such a calamitous failure?

Parenting 101 is the need to give children space to make mistakes.  It may be excruciating to watch, but true growth requires the opportunity to fail.  King Solomon put it this way - "the righteous fall seven times only to rise" (Proverbs 24:16).  Failure is a prerequisite for greatness.  Mistakes are necessary.  All we need is resilience to rise and an abundance of patience for ourselves and others along the way.