For many disorders, the extent to which they apply on an axis is also, when it comes down to it, defined relative to whether it causes trouble for one's job or not. This is written explicitly into many of the diagnostic criteria, so that the same objective behaviors would be a disorder for a person with one job, where they pose a serious problem to their ability to carry on that occupation, but not for another person with another job, where the behavior is no threat to their livelihood.

But this begs the question [1] of whether it's the person or the job that's "at fault" or "abnormal". That's where some of the criticism originates: one allegation is that perfectly normal people are being diagnosed as mentally ill and told they need treatment, when they are maladapted to a job that in fact most humans are maladapted to. In other words, they are within the normal range of human behavior, but treated as mentally ill because their job expects abnormal human behavior.

[1] In the precise meaning of the term.