When we first had a shower fitted, I would use it to rinse shampoo out of S's hair when she had a bath. She was wary of it to start with, but then would cautiously walk towards it to stand under the flow of water.
One evening S was particularly mucky after tea, and it was a bit late to be messing about running a bath so I thought I'd give her a shower... and it was a massive hit! She's not had a bath since!
Over the last month or so, we've settled into a nice little routine: S has her tea and makes as much mess as is humanly possible. Then I carefully lift her from her high chair and try to get her up the stairs without getting too much food on me or the floor, and she runs to the bathroom, clinging to the edge of the bath while I try to get her clothes and nappy off her, while she tries to lift her leg over the side of the bath. I'm concerned it'll only be a couple of months before she's able to jump on in before I'm able to get her clothes off!
So any way, we take her clothes off, and then make a big kerfuffle of jumping into the bath ("one... two... three!") and she runs under the stream of water... and my work is done.
S has suffered with a sort of low-grade eczema for about a year now. Nothing bad enough to cause distress, just random patches of dry skin. We tried creams from the doctor and emollient bath oil that just made the bath dangerous. We had some success with putting porridge and coconut oil into the bath, but it was messy to clean up and just a general pain in the arse. Since S has been having a shower instead of a bath, and I've stopped washing her hair because the water washes all the food out of it so there's no need for shampoo, there has been (touch wood) no eczema. Her skin is as soft and squishable as it ever was.
S will spend as long as she's allowed running up and down the bath, standing under the water and then wandering off to the other end, then coming back to put her face under the water. Back and forth, back and forth. My bath takes forever to drain, so once I switch the water off, she then has another 10 minutes or so of splashing about before getting out.
It doesn't matter if S is feeling rubbish, teething a bit, has had a bad day, is over-tired. She absolutely loves to have a shower. We no longer fight to make sure she's washed all the food off her face, or fight to get her hair washed, or fight to make sure there's no more "washable" pen on her hands/arms/legs/face/belly. I just let her stand under the shower and it's all taken care of. With endless giggling and shrieking. Perfection.