Every human being must proceed upon a path of personal and communal growth, one of going from katnut (immaturity) to gadlut (maturity).
We must make mistakes, learn from them, and grow. It is through this process that we achieve a higher level of true bitachon (absolute trust) in Hashem and in His absolute sovereignty.
Am Yisrael had to go through these challenges in order to be able to completely surrender to and rely upon HKBH, recognizing that He is the One who manages everything. This is the challenge posed to all humanity – to give up our illusion that we can control our reality.
We must act within the natural order of the world, do our hishtadlut (make a normal amount of effort), but then surrender the results completely up to HKBH knowing that it is not by our might that we accomplish, but by His.
We merely make a vessel for His blessing to be fulfilled.