But surely both the location of the "zero" hue and the directionality of where it goes from there are both arbitrary? I didn't know red was 00 until you mentioned it.
It makes sense in terms of physics. Start at 0, red, the beginning of the visible spectrum, and the number increases along with the wavelength, all the way through violet, the other end of the visible spectrum.
Sadly, after hue goes through violet, it then disappears into magenta, which isn't in fact a colour on the spectrum at all, before arriving back at red when it reaches 1.