Check out Best-Sellers Initially Rejected posted at Literary Rejections Official Website.
Yes, it is comforting to read about how writers went on to successful careers after having been rejected, but it is too easy to simply blame the rejection on the editor or agent not appreciating the manuscript.
It's true that manuscripts are rejected for a variety of reasons: it's not a good fit for an editor's or agent's interest, a similar work has recently been contracted or published, etc. I want to be as sure as possible that the quality of my writing isn't one of those reasons.
The fact that caught my attention in the post was that authors remarked that they had done a revision as a result of having their manuscript rejected.
I always look at a rejected manuscript for ways to improve my work before submitting it elsewhere.
An opportunity for a rewrite creates a better manuscript. I can evaluate my work from a fresh perspective when some time has passed between readings.