IMHO and XP, in our line of work as solopreneurs, nomads, remote workers, business owners we need to wear all the hats, not only as a pm or dev, but also marketing, sales, accounting, finance, support, qa, hr... if you are in it alone you may only be able to count on yourself, in the end its your business, your product. Of course once you can afford it you should delegate all those responsabilities that you know are better done by others, but if you dont understand how they operate or work, sooner or later it might comeback to bite you.