Evan Schuman's StorefrontBacktalk

And when an item is nearly out of stock, a close watch on inventory doesn’t help. Customers abandon shopping carts or remove items from their carts, and there’s no way to know how long it will take for a customer to go from selecting an item to checking out. As a result, items are likely to flicker between in-stock and out-of-stock until they’re all definitely, for-certain gone.

How can you handle that? There’s the brute-force method: Wait until the customer checks out and then, if the item is truly sold-out, make the item disappear from the shopping cart. That’s one of the things some customers complained about on Missoni Tuesday.

Alternatively, you could count items out of inventory as soon as it’s in a basket. That way merchandise will appear to be out of stock sooner, but come back in-stock as customers decide to remove items from their shopping carts or simply abandon them. That way there’s no checkout-time surprises. But customers who repeatedly refresh or revisit an item’s page will see it go out of stock, then back in, then out, then in again.

Or you could try to manage those almost-out-of-stocks statistically, hoping that a certain percentage of items in shopping carts will be abandoned. That’s essentially why airlines oversell flights. That works well, doesn’t it?

Another approach is providing more information for customers while they’re shopping, warning them that some item in their cart is nearing out-of-stock status and might not be available at checkout time. That will get rid of the unpleasant surprise from evaporating items.

But it’s also likely to make customers cut their online shopping trip short, so they won’t risk losing the almost-gone item. The longer a customer stays in the store, the more likely he or she is to buy more. Rushing customers doesn’t help on that front.

Worse still, all that extra information keeps reminding customers that in an online store they don’t really have items in their shopping cart. The cart isn’t real, the merchandise isn’t real and, until it’s delivered, they can’t really trust that they’ve bought anything.

That’s exactly the opposite of the direction you want to lead customers. You want them to feel like in-store, online and mobile commerce are all pretty much the same. Anything that points up the differences isn’t something you want.

You can’t win, at least when supplies of an item are running low. They’re all problematic choices. And the irony is that the better the inventory system an online store has, the more problems those choices are bound to cause.