We have been asked to show what we do when we say "stock work". I do stock photography. I have been doing it since late 2014. In January 2015 I had around 15 images on Shutterstock. I had made around $5 by that time. But it was fun and a huge learning experience. When I got photos rejected, I took the time to look and learn.
All stock agencies are different. Some are super strict, no noise at all, and you need to show super sharp focus on your images.. As I got those rejections, I didn't give up, I just kept trying harder. It has truly helped me grow as a photographer.
I submit to 5 different agencies now. All have regular sales for the most part. Finding models that are willing to let you sell their photos is tough. Most think we get paid high amounts of $$. Unfortunately, the average commission from a stock sale is 25 cents. Yes....cents, a quarter. Those photos are used for a blog or a website. Sometimes you get lucky and get the higher sales which can range from $20 to $250. I have had a few of those. But..... even though a quarter is all you get, they sell well and they add up.
A lot are photos that sit on a hard drive and would never earn a dime just sitting there. Once they are there, they are there.