Why would my multi-speed fan switch operate at reverse strength?

The story thus far:

I ended up removing the non-ceiling-fan-rated junction box and brace from before (after 5 trips to various hardware stores in different attempts at a solution).

I was able to hang the ceiling fan, only to realize that I couldn’t turn it on. After calling 7 different ceiling fan stores I was able to get a fan wall switch for my model.

Then I realized that the reason the original dimmer switch didn’t work was that it had been wired incorrectly. Thanking my lucky stars for playing with circuits as a kid, I rewired the new switch into the wall, at which point the fan turned, but made a horrible sound.

Once I opened up the rotor to attach the fan blades, I realized that there was styrofoam surrounding it. So I took that out. But the the motor wouldn’t turn when I turned on the switch.

Turns out the forward/revers switch had been jiggled so the clutch was disengaged from the fan.

Now the fan works from the switch and operates in both forward and reverse with nary a whistle. The only strange thing is… the switch is marked 0 (off) 1 2 3 4. In both forward and reverse, 1 is the strongest setting and 4 is the weakest. Weird, right?

Is this some wiring polarity thing? Or just a practical joke by the makers of ceiling fans?