It honestly varies from case to case. Sometimes I like WIPS because their roughness conveys more action/emotion/what have you then do the cleaned, finalized versions. Or people will post sketchy things that look amazing and, since they'll never be finished, that is the only way I'll ever get to see that particular idea.

On the other hand, it drives me mildly nuts when people post, like, 5 WIPS of a single image. At least throw all the WIPS into a single image, goodness--I like seeing original sketchy ideas, not the same one over and over with every itty bitty little tweak displayed. ;___;