Should I sell on a marketplace or my own store?
Updated
What you are really trading
A marketplace rents you its traffic, and the rent is a larger cut, less control and no direct line to the buyer afterwards. Your own store costs less per sale and gives you the customer, but every single buyer has to be found by you. That is the whole trade.
If you have any audience at all, you are usually renting traffic you already had.
Choose the marketplace when
You have no audience, your product fits a category shoppers already browse, and you can live with the rules.
It is the fastest route to a first sale from a stranger.
Choose your own store when
You have any audience at all — a newsletter, a community, a following. Then you are paying marketplace rent for traffic you already had.
Also choose it when your product does not fit a browsing category, which is most business products.
Using both properly
Marketplace for discovery, your own store for everything after. Include something in the download that invites the buyer to your list.
That way the marketplace is a source of customers, not the owner of them.