Talk about dropping the ball. Best Buy waited until as late as this week — mere days before Christmas — to admit that it’s not going to be able to fulfill the online orders placed by some customers. These are customers, by the way, who made their purchases around Thanksgiving weekend, more than three weeks ago.

How many customers — make that former customers, most likely — has Best Buy let down? The retailer won’t say. But it did release an apology, stating:

“Due to overwhelming demand of hot product offerings on BestBuy.com during the November and December time period, we have encountered a situation that has affected redemption of some of our customers’ online orders. We are very sorry for the inconvenience this has caused, and we have notified the affected customers.”

In other words: Whoops! Our bad. Happy holidays!

Why did Best Buy wait so long to fess up? Why did it accept the orders for laptops, digital cameras, video games and other out-of-stock items in the first place? That info, like the exact number of affected customers, hasn’t been made public.

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But the news of Best Buy’s holiday-season failure is spreading quickly, and it will surely be remembered by plenty of affected and nonaffected consumers alike. Here’s an analysis courtesy of the Minneapolis Star-Tribune, which covers Minnesota-based Best Buy closely:

“Personal disappointment will go along with this, and it will be remembered,” said Dave Brennan, co-director of the Institute for Retailing Excellence at the University of St. Thomas. “From a publicity standpoint, this is devastating. You have to ask yourself, ‘Are people likely to go back to the same source or go to other sources the next time?'”

Retail expert Brad Wilson, of BradsDeals.com, told TheStreet.com that he wasn’t all that surprised that Best Buy is disappointing customers by canceling the orders:

“We have come to expect something like this when they promote aggressively,” Wilson said.

The site dealnews, meanwhile, recently gave Best Buy top billing on its dubious list of retailers to steer clear of for last-minute online shopping. “In gathering suggestions for this list,” the post reads, “Best Buy was one of the most frequently named.”

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As for the affected customers, the online forum at BestBuy.com is filled with comments from outraged shoppers, who are most disappointed not because mistakes were made or orders were canceled but because of how Best Buy mismanaged the situation. For example:

Everyone makes mistakes, but it’s the ones who refuse to acknowledge their mistakes that just make me feel like I’m banging my head against a wall … Absolutely unacceptable the way this has been handled.

Another shopper, who had ordered a $350 laptop from Best Buy on Cyber Monday and found out earlier this week that it would never arrive, wrote a letter to the company, which was partially excerpted by the Star-Tribune, that read:

“As a Minnesotan I preferred to do my business with a Minnesota-based company. But I can say with honesty that I won’t shop at Best Buy again.”

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Say what you will about those fanatical Black Friday shoppers — you know, the ones who camped out for more than a week in front of Best Buy stores in anticipation of door-buster sales. Maybe they knew something the online shoppers weren’t aware of. Namely that, as this incident indicates, when you’re dealing with Best Buy, you can’t be 100% sure the retailer has the item you want until you’re actually holding it in your hands.

Tuttle is a reporter at TIME. Find him on Twitter at @bradrtuttle. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.