I read somewhere that writers (presumably of short fiction) should strive for 100 rejections a year.
This sounds harsh and counter-intuitive, but not submitting because of the inevitable rejection is like a software developer never going live because they fear someone will find a bug in the code (and they will) or because potential users won't love it. Developers write it anyway. They go live. They know more people will reject the program than embrace it. This is life.
I'm going for 100 in 2017. One down, 99 to go.
(I will post a link to the article when I find it.)