A product manager should ideally be a generalist. Yes, some specialization is required, but in what area? Statistical analysis of research data so you can draw better conclusions? System architecture so your feature specifications make more practical sense? Front-end programming so engineers don’t rebel against you? Graphic design so you can faithfully model the product? The short answer: all of the above and much more. Needless to say, you also need to be a pro at project management and people management (even if you don’t have direct reports.) Having poor knowledge of what’s really going on and relying blindly on others is a recipe for disaster. You must work well with others and be self-sufficient at the same time.
To test how good a product manager you are, ask yourself: can I replace any of the stakeholders I work with on a daily basis and be reasonably good at it? And will I become really good after six month in that role? If the answer is *no*, identify your weaknesses and work toward improving. One way to do so is to actually take some of their responsibilities. The best way to learn is by doing, and the best way to do anything seriously is to have a deadline and work on a real product or service. Offer your help without stepping on anybody’s feet and you’ll be surprised how cooperative even the most aloof and unfriendly people can be.
To drive progress, researchers need to become increasingly specialized and engineers must focus on particular technologies. Product managers don’t have this luxury, and have to remain equally comfortable at everything they deal with – sales, marketing, engineering, quality assurance, or what have you. Increased complexity makes their lives difficult but not impossible. They don’t need to excel; they just need to speak the language and know enough to be dangerous (and then some.)
The best product managers are Jacks of all trades and masters of *all*. This allows them to delegate effectively, being able to trust and verify. The biggest time wasters are people who earn your trust and don’t deliver, selling you stories instead of results. It’s ultimately your fault, however; you should sense that something is wrong and realize what’s going on well before it’s too late. Not understanding what the other person is doing is a feeble excuse. If you use it too often, product management is not for you.