By heating the water on the stove the quantity of hot water gets limited and thus having a hot shower is ruled out.
Why Electric water heater is better than heating the water on the stove?
Heating the water on the stove is tedious and time consuming where as you just need to switch on electric water heater to enjoy unlimited hot water.
Heating the water on the stove needs to be manually switched off hence if left unattended can be hazardous.
Heating the water on the stove is not safe as there is a possibility of water spillage while transporting the bucket of hot water to the place of usage.