Failures / Errors when analyzed always makes oneself better. Such a simple statement has lead to the development of one of the most profound theorems in statistics. Here is a little note on how Central Limit theorem, a theorem which almost everyone intuitively uses, came to existence:

“The Central Limit theorem was originally stated and proved by French Mathematician Pierre Simon, who came to this theorem from his observations that errors of measurement tend to be normally distributed. The application of CLT to show that measurement errors are approximately normally distributed is regarded as an important contribution to science. Indeed, in the 17th and 18th centuries, the CLT was often called the “law of frequency or errors”

In the words of Francis Galton :

I know of scarcely anything so apt to impress the imagination as the wonderful form of cosmic order expressed by the law of frequency of error.  The law would have been personified by the Greeks if they had known of it.  It reigns with serenity and complete self-effacement amidst the wildest confusion.  The larger the mob, the greater the apparent anarchy, the more perfect is its sway.  It is the supreme law of unreason.”