It actually makes sense, I think. The bottleneck (bar, qualifying exam) keeps the supply artificially low, so those who pass and qualify are always in high demand (low unemployment). Those who don't pass either try again, or after a while go into other fields and no longer consider themselves prospective doctors, lawyers, etc. It's sort of like the effect where, during a prolonged recession, unemployment numbers 'drop' because some people give up actively looking for a job, and are no longer counted.
Sure, I should have specified that I'm also counting people who have the skills and training, but aren't allowed to practice (such as people who failed the medical or bar exam). It makes sense to me to consider those "prospectives" as unemployed in their profession (especially since those professions take years, in some cases as much as a decade, of specialized education, all before the exam itself).
