Comment by FarmerPotato

Funny! Users see knobs and think that it sounds better!

Like @walrah says, knobs don't obviously fit mouse movements. I could imagine a touch screen version that makes sense. Sliders match more closely. Little up/down arrows are too small. Utilizing the scroll wheel could make sense.

Finally, a digital number would be easier to read at a glance.

Still, I like analog knobs (sliders are ok). I bought a little Arturia keyboard with ten knobs. Which I haven't figured out how to assign...

I remember researching X11 Input Extensions, when KNOB was a device category. Used those on a VAX.