Every blender I've had in my kitchen had at least 10 speeds on it. All were labeled with interchangeable words, none of which meant anything, all of which might as well have said, "Warp 9."
@georgetakei
What is this concept of "constant rainfall rate"?
I've spent (counts) YEARS under canvas and tin(-plated, yes) roofs and ... rainfall varies, irregularly.
So, one speed is temporarily appropriate.