Success teaches us nothing; only failure teaches.

Source: This quote is from an address by Hyman G. Rickover, delivered to US Naval Postgraduate School on 16 March 1954.

You have to learn from the mistakes of others. You won’t live long enough to make them all yourself.

Source: This quote or it’s variants are often attributed to Hyman G. Rickover, Eleanor Roosevelt, Samuel Levenson, and Lao Tzu, but no authentic source for these attributions is yet found.