My kids never had any issues with the areas directly around the pool; however, I've walked up the stairs near the pool to where the slide starts to go to Artist Palette a few times and to me personally, sometimes in the busiest times of the day, the stairs can get slippery. There seem to be about 1/2 the pre-teen/teen kids running up the stairs to go down the slide (and repeating this again and again), which means that they sometimes are almost running up the stairs. I did see one boy around 10 years old slip on the 2nd or 3rd step up when doing this.
I just thought - he's lucky that he was only 2-3 steps up or he could have really gotten hurt because he did slip and fall to the bottom. I don't know how old your kids are, but if they do the slides, I'd just maybe watch a little closer if they take the stairs, esp in busier times when the stairs are totally wet. We always tell our kids to take the stairs slowly, but when they see older kids racing up the stairs, I think they feel tempted to go faster, too.
HTH!