Many artist create hundreds of totally random works of art but others choose to create a series of work.
(Definition) Series: a number of usually similar things done, produced etc one after another.
For example an artist might create a series of Dogs, instead of dogs, cats, and elephants. That way the work can be specific and more in depth, the series can get even more focused to a specific breed of dog and dog color. This helps artists to explore different ideas on one topic, and relate to their audience. An audience is more likely to follow you if they can understand where your art is coming from, instead of just a pile of work that is all over the place.
An art series can also be a certain art style such as pointillism, or any subject/theme. Then research your subject because you need to create at least ten images. Study, talk to people you know, do what you need to do to perfect the series. Even if you know the subject, the final image will reflect your knowledge. Gather reference images, photos, and even take some photos of your own! Break it down to the best 10 images, when I start a series I gather as many images as possible that are great quality then I tinker with the lot until I get the best that I will paint. Create a schedule for yourself and commit to it. I often paint 1-2 paintings a day depending on the size of the canvas, I also create a deadline which helps push me. Get your supplies and commit, you know yourself best.
This Gallery show my most recent series.
A series can also be a collection of a specific type of subject or many style of the same subject, If I did a series on say French Landscapes I could start with this painting:
Moving on to a broad range or staying in this one pond.
Here are some france landscape paintings for sale including the piece above.