The danger of having a leaky toilet is that, if the leak goes unnoticed or not repaired, it could damage your bathroom floor and sub floor, and it could spread the damage downstairs if your bathroom is located above. Old toilets are not efficient, they waste a lot of water, thus increasing your utility bill. Flushing a new toilet will only use 1.5 gallons of water, versus 7 gallons of water for the old ones. That’s 450% more water consumption than normal. It makes perfect sense to install a new toilet, beautify your bathroom, preserve water while reducing your utility bill and preventing potential damages to the house.