Seems pointless and inconvenient for me as they usually seem to be poor quality, and can you really listen to music in the shower, and are you showering long enough to benefit from it?
Or do you own one and use for a different purpose, like swimming or Kayaking?
I use a cheap little speaker pretty much every time I shower, but I tend to listen to music whenever I’m getting ready anyway. Because it’s a cheap one, the sound isn’t amazing, but when I’m in the shower the other noises drown a lot of the sound out anyway, so it doesn’t really matter.
I’m disabled though, so I tend to get in the shower after my wife and kid have left the house, and I take a while. If I shower in the morning, my washing and dressing routine can take close to an hour, so it’s not like I’m jumping in and out before the first song has the chance to finish.
I hadn’t thought of listening to a podcast or audiobook while I’m getting ready though, so that might be worth a try :)