Normal Wainscoting can get slightly wet but not too wet.
Most Wainscoting is made from plywood which can separate when the board gets wet so while you can use Wainscoting in a bathroom without a problem it should not be allowed to get wet.
They do make Wainscoting that is designed to get wet without any damage being done to it.
Also Wainscoting should not be used outdoors and instead should only be used indoors.
Wainscoting when installed properly gives a house a nice look and can also increase the value of the home.
I installed Wainscoting in my house about 5 years ago and it looked lovely and when I sold the house I profited an extra $10,000.00 just off of the installation of the Wainscoting.
The house also sold much faster with the Wainscoting.
I now live in the country and had a house built and also installed Wainscoting which is a very great look to the house.