Electrical short circuit happens only if the liquid is conductive. I know of a lot of pianos that can take a pint or two. Sticky yes... broken no. Some of them will play everything at full velocity until they dry completely. And some stop working until they dry.

Most circuits in modern keyboards use short-circuit and reverse polarity protection.

Also many low voltage circuits can also function fully submerged in water.

I've even seen computers cooled by submerging the electronic parts in liquid. Both water, oil and other coolant solutions.

DocZ