Stereotyping westerners for doing that is the wrong thing to do, as not just everyone who lives in the west does that. Pretty much everyone from every part of the world does it - and there are some who don't, as some westerners do not do this. It is just easier to leave the water on then turning it on and off and on and off every time the person has to put their toothbrush down.
On average, a person uses about 1-2 gallons of water while brushing their teeth. However, turning off the tap while brushing can significantly reduce the amount of water wasted.
Conserving the water when you turn off the faucet when you brush your teeth.
Turn off the water while brushing your teeth until you are ready to rinse.
On average, a person wastes about 2 liters of water per minute while brushing their teeth with the faucet running.
You would be being frugal (careful in spending or using something) in using the water.
By saving water, air, gas, and resources. Take small steps like turning off the tap while brushing your teeth.
30000 gallons
About a half cup
Luke warm
Depends if you are running the water while brushing your teeth. Otherwise around 1-2.5 liters of water
Individuals can conserve water by taking shorter showers and turning off the tap while brushing their teeth.
By turning off lights when your not using them, turn off water while brushing your teeth. Also you can air dry your clothes instead of putting them in the dryer.