Perhaps a better analogy is Newton's cradle: https://en.wikipedia.org/wiki/Newton%27s_cradle

The ticking beads don't really move but transfer energy to each other. That's maybe a more useful analogy than the notion of beads or water moving through some pipe.

I'm not a physicist of course but I get that what was explained to me in high school (many decades ago) was probably a bit of an oversimplification. Ticking beads lose some energy as they smash into each other. Hence thin wires heat up and glow.

This is probably cringe-worthy enough for anyone who actually studies this for a living; so I'll stop right there ;-)