Correct, however since you don't have to pay for the electricity to keep 50 or 60 gallons of water warm to hot 24/7, and pay to heat it back up after using all the hot water in the tank, on demand tankless WH save money. Yes, it does take a little longer to get hot water from a faucet, that's because the water that is setting in the water pipes after the tankless gets cold. So you get cold then hot. Does not take a long time to get hot water. They do have to be properly vented and installed per manufactures instructions and the outer surface of the tankless gets very hot so it needs its own closet with incoming air vents. Excuse me, combustable air venting.