@futurebird My rationale: it's a machine that produces cold... if you want more cold, you have to make the machine work harder, therefore you turn it "up". i.e: 10 is colder than 1.
It's a bit dumb, and certainly open to misinterpretation. I posit that a dial with temperatures would be more sensible, and has probably been within our technical grasp for a while (pretty sure it's on more expensive fridges!).