The new site Jet was meant to be the e-commerce version of Costco, charging users a $50 annual fee (which they later dropped) in exchange for excellent discounts on a wide variety of merchandise. This is Jet’s first holiday season, and the good news is they have a lot of business. Unfortunately, that means that they can no longer guarantee delivery by Christmas.

This is actually rather smart of Jet: they’ve learned from the mistakes of other retailers, and aren’t over-promising delivery by Christmas to gift-givers who will be disappointed. It means losing out on sales, though, since most of their gifty items come from those other warehouses.

Jet’s business plan, which we’ve called either an overambitious and doomed wacky scheme or the future of retail, using complicated calculations to optimize shoppers’ virtual baskets and offer them discounts if all of their items come from the same warehouse.

A shipping window of five to seven days is longer than most other retailers, including Jet’s archenemy Amazon, but there’ san upside: when they’re able to deliver any faster than that, customers are delighted.

“Because it’s our first holiday season, we erred on the side of preserving a great experience for our members by communicating super early about any potential impacts caused by industry-wide delays,” a company spokesperson told USA Today.

While Amazon is looking to depend less on outside partners like UPS, Jet is doing the opposite: while they do have their own warehouses, they’re depending on a nationwide network of other sellers to fulfill orders for other items. That’s good for expanding their inventory super-fast, but not as good at the end of the holiday season, when last-minute shoppers roam the Web.

Jet.com says it can’t guarantee Christmas delivery [USA Today]

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