Product selection could very well be the quantity one reason many people fail in Amazon FBA. A new vendor may hurry through 1st part of doing product study to pick the first product in which determines good, and is available. Proper they go to list the item they recognize the merchandise just isn't providing very well at all. They discover quickly enough that there's sometimes too much competition for the buy box, or even hardly any need at all. And/or more serious that they couldn't verify in the event that product had been available and shipped by just Amazon themselves!