Why is range used as default constraint in distance member of a modifier

Inside standard.osc (line 972), the distance member has a default constraint inside a range, making this default value unusable in a concrete scenario. Why did the standard choose this constant of 10cm offset to either side, instead of the reasonable 0, which would not prevent the use of this default in concrete scenarios? Now, an implementation that only accepts concrete scenarios will have to cope with this range in the standard.osc file.