Make Sure You Have Enough Supply on Hand to Meet Demand

One of your early financial outlays for your e-commerce venture will be to purchase or make enough inventory to meet the initial demand. At the start of your venture, you probably won't know how much of each item will sell, so you'll want to play it safe and keep a good amount available. Over time, you'll have a better sense of how quickly each product sells and how much of it to keep in stock, but in the early days of your store, you're going to want to make sure you can meet the demand. Nothing is worse than turning a customer away because a product is out of stock or selling a product that you don't have and being forced to delay shipment while you wait to restock!

(MLA 8th Edition)