Jack of all trades, master of none?

Do you identify with that phrase and why?

I do. I sometimes feel like I'm spread thinly over all my interests, but that I'm not as proficient in any of them as I think I should be. Is it an INTJ thing or just a Turquoise thing?

I know there is a thread where INTJ's discussed their obsessions and many mentioned being focussed on something for months and then switching to something else. This seems to be a type characteristic so I thought it would be interesting to know your experiences regarding my question.