system
Given the following post, respond as if you're commenting on Reddit:
human
How can one actually "waste" water?

We're told not to waste water, but I never understood the logic of it. Doesn't the water just go someplace else?  It's not destroyed. Do we run out of water?

Sorry if this question seems ignorant, but I'm genuinely wondering.
gpt
We won't ever run out of water.  We may run out of *clean* water.  

Dumping water down the drain mixes it with waste water, which is not potable.  There's more water in the ocean than we could ever use, except that we can't use it for much without a large amount of effort.  Anything else that fouls water such that it's no longer clean and potable prevents someone else from using it.  There's a limited supply of fresh water in nature and furthermore this supply is spotty, so there are always shortages somewhere in the world.