IOW, I understand your qualification to mean a well though out design will tend to only need changes to it's meta-data than in the actual code

Well, that is certainly part of it. But it also has to do with how much code rework is needed per change. For example, in program A, a given requirements change may result in splitting 2 classes and moving 2 methods to another class; but in program B, the same change may only result in altering 2 classes in place. The second one would probably get a higher "change-friendly" score. (There are finer granularity counting techniques, I would note.)

It is based on the total effort of rework you could say, regardless of whether it is code or tables that have to be altered. (Note that meta-data alteration may require a less skilled person, and thus less money expended by the company.)