In the modern work few operations are one-man shows, specialization is the name of the game. Find your niche whatever it may be and work hard at it. Nothing wrong with random hustles if you discover you enjoy it or are good at it or both and it makes you enough to survive and then thrive. For example marketing techniques can be applied in many situations and knowledge can be built on over multiple "failed" attempts. Any situation where you end up learning what to do and avoid the next time around is actually a success.