When you grow up expecting things to be a certain way and find out they are not a universal constant, it can be quite bewildering, and when that bewilderment is applied to plumbing, things often get unpleasant.
To travel in a land where, for example, toilet paper cannot be flushed, when one is used to flushing, is not a happy experience, and yet if chucking it in the trash is what you’re used to, why would it seem disturbing?
That said, there is something in this video presentation by Tom Scott—in which the reason why British sinks are (or more correctly, were) always plumbed with separate hot and cold taps, with no mixer on top—which is nasty from any perspective.
Although… don’t most people run the cold tap for a while, just to flush out the room temperature water in the pipes and get to the cold stuff from the mains?
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