Programmers is for questions about software development and being a programmer: career advice questions are off-topic here unless they uniquely apply to programmers.
That is, they hit the blue part of this diagram:
Most don't: there are a great many things about careers that are applicable to any job, which dilutes the core focus of this site and diminishes the value Stack Exchange brings to the Q&A space: focused sites filled with experts on that one particular subject. Programmers's expertise is software development, not general career advice.
However, there is a proposal in the works, Professional Matters, that will invite experts on general career and workplace questions. It's currently in the commitment phase: with a few more committed people, it'll launch.
Beyond the scope issue we get into problems that are just unsolvable in the Stack Exchange Q&A format: particularly questions where the asker wants someone to tell them what they should do given a broad situation. Those questions aren't going to fit here or Professional Matters, regardless of topical scope. We simply don't know the person asking well enough to provide meaningful advice to their specific situation.
For more about this problem, check out:
Are Career Advice questions useful to anyone except the poster?
As to why an inordinate amount of questions in the career tag (also, jobs, advice) are closed: we deprecated them in favor of more specific and meaningful tags a few months ago:
Posse request: jobs/career/etc. tag cleanup
So, career-tagged questions are either:
- Good, on-topic questions that get retagged; or
- Off-topic questions that are closed and left to either be substantially improved to become on-topic or deleted
Since we've been fairly vigilant about the former category, the end result is a tag that's more or less a wasteland. We've tried various tactics to clean the tag up more quickly, but we haven't found a magic bullet yet.