This hits hard based on my experience in academia.
In graduate school I was strongly advised to set aside "big" problems and focus on safe low-hanging fruit--derivative projects or incremental improvements to existing work--that will result in a steady stream of (mediocre) publications. The situation is the same for postdocs and even tenure track faculty at research-focused institutions. Only after you get ~15 years into your research career (and receive tenure) are you really free to focus on original work, which tends to be high risk and high reward.
(Of course you can do that earlier, but there's a high chance your career won't advance on schedule, which is very bad.)
In graduate school I was strongly advised to set aside "big" problems and focus on safe low-hanging fruit--derivative projects or incremental improvements to existing work--that will result in a steady stream of (mediocre) publications. The situation is the same for postdocs and even tenure track faculty at research-focused institutions. Only after you get ~15 years into your research career (and receive tenure) are you really free to focus on original work, which tends to be high risk and high reward.
(Of course you can do that earlier, but there's a high chance your career won't advance on schedule, which is very bad.)