I was once a slush pile reader. For nearly five years, I worked for the much-lamented, now-defunct Kansas Quarterly Magazine. I had a rather glamorous title: Editorial Intern.
On the ground I was a more pragmatic thing: eighteen and in charge of hauling the vast boxes of slush pile submissions from the university's mailroom to KQ's office.
From there it was also my thankless task to open all the envelopes, enter the submissions into a rudimentary database (Wordstar!), and perform the basic task of deciding which submissions were worth passing on to the editors. This was in the halcyon days before the internet, back when many magazine editors sent personal rejection letters for every submission they read and rejected.
As the person who typed those notes on a manual Underwood, it was in my best interests to be sure the editors didn't read any more manuscripts than absolutely necessary.
I rejected with brutal efficiency, sometimes on grounds as frivolous as excessive scotch tape usage on the envelope. Don't blame me. We were always behind, hopelessly inundated with submissions. Expediency was the better part of valor.
For many years it was the memory of those rejections that kept me from submitting work to magazines. Fear of karmic retribution. It has abated somewhat, but not disappeared entirely.