Does the ground (ceramic) become pure from urine if it dries, knowing that my mother wipes it with a damp cloth and is not convinced otherwise?

The ground and whatever is firmly attached to it becomes pure through desiccation, according to many scholars, and there is no harm in acting upon this opinion. However, if the urine does not dry, it must be washed, and merely wiping it is not sufficient. The spot does not need to be purified unless one intends to pray on it.