So far this year (and remember, it's only February), I've judged the RITA entries I was assigned to, judged the entries in my local chapter's contest for unpublished authors, and am waiting for the entries in the Hearts Through History contest for unpublished authors.
Why do I so willingly give of my time to judge contests? The answer is very simple. The feedback I got from contests helped me become a published author, and I want to return the favor. Besides, with the RITA entries, you have no choice. If you enter a book into that contest, you must read some entries. It's a huge contest, with 2,000 entries, all needing five judges each. Imagine the logistics nightmare the RWA staff has each January.
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But I have to throw out a note of caution in both instances. Chances are the person reading your work doesn't write in your particular genre, and if that's the case, their remarks should not be considered gospel. Their overall impression of your work–fine–but individual remarks? Not so much. I recently had a case where the work I was judging was set in ancient Scotland. I know nothing about the era, other than what I see on the Outlander series, so some of the words tripped me up. I had to put in my notes to the author that I was unschooled in her particular genre, so she should only consider my overall impression of her work. And then, someone who was remarking on my work–a historical set in 1860s America–referred to a medical condition that has only been diagnosed in the past twenty years. Again, I fact-checked my work and found that, in this case, anyway, I was correct.
The moral of this story is this–your work needs to be viewed by someone other than your family and friends, in order to get constructive criticism, and contests and workshops are a very good way to accomplish this. But not everyone who offers feedback is competent to do so.
A grain of salt needs to be added in each time a person gets a contest entry back with comments. But you should enter your work, and get back comments. It will only improve your writing.