Completed WIPs (works-in-progress) are similar to step-by-steps in that they show the progress of a painting from start to finish. No explanation or text accompany the picture posts. But you can always comment or ask the artist about the painting or techniques that you see from one post to the next.
We started posting WIPs when we received feedback from some of the students/beginners in the medium that they feel overwhelmed sometimes seeing all the finished paintings posted. Some said they do not know how or where to begin a painting. So we thought, why not share a painting's progress. Perhaps when they see the procedure broken down into doable sections, it will make watercolor painting less daunting.
WIPs may come as a series of posts by the artist as they finish in real time, or as a set in an album.