[int_19h]

Yep, so it doesn't "just happen" - you need to build a pump first, and you need to keep it running for the water to flow uphill.

But it can be done.

[MichaelZuo]

The switch for the water pump, electricity connection, etc., must necessarily be centralized.

It's impractical to design a pump operated by millions of switches or fed by millions of electrical cables.

[int_19h]

It's less efficient, sure. But it's eminently practical if your goal is to avoid hydraulic despotism long term.

[MichaelZuo]

It would be so less efficient that you could simply buy a 1000x more water pumps for the same price. No one sane would choose a water pump with a million switches over 1000 of the same pumps with 1 switch each.