If you want to control something, you have roughly two ways:
The first relates to Science, it is the SCM way. The other relates to Organization, it is the Process way.
In theory, the two ways are independent, orthogonal. They may coexist in peace and are not concerned with each other. In practice however, the collisions are inevitable. The alternative is:
The problem is that they interfere in what is eventually done. Or the Process way does -- the SCM should not, or as few as possible.
Of course, one could say that in order to enable the scientific management, some minimal process must be followed, and this is true; although more than of "process", it should be a matter of collaboration, of conventions.
But this should again --from the SCM point of view-- be minimal, and be itself managed in the same way. SCM --as science-- must be reflexive. In practice, processes soon clash with SCM: more process is less management.
The issue of "definition" must be dealt within this context.
Definitions are a Process concern. Science preferably uses
"theories", and what makes a theory scientific is that it is
"defeasible", i.e. that it should be easy, obvious, and
non-controversial to prove it wrong, on an example.
This explains that it is not an SCM issue that the very definition of SCM is not straightforward.