Amazon Go’s cashier-less grocery stores have hit a small snag, namely that they’re not very good at selling people food just yet. The company’s Just Walk Out technology is supposed to streamline the shopping experience to the point that you just grab an item off the shelf and leave with it, but the online retailer’s dream will take just a little longer to become reality.

The company is reportedly delaying the opening of the flagship store to work out some glitches in its technology. The stores were supposed to open to the public in late March, but it’s unclear when they’ll start selling now.

The problem seems to be item tracking, which is also the whole crux of the store itself. When the store starts to get more than 20 people shopping at once, the complex system of cameras and other sensors has trouble keeping track of where everything is. According to the Wall Street Journal, if customers (Amazon employees participating in the testing) pick things up and put them all in a common basket, walk around with them, or put them back on the shelf where they’re not supposed to be, it quickly becomes too much for the store’s brand new tracking system to handle.

This is, of course, exactly why the cashier-less store has not been tried in the past; companies would love to phase out this enormous part of the workforce, they just haven’t been successful in doing so. It’s been tried many times with self check-out options, but these cause frustration and it arguably takes just as many employees to fix people’s mistakes as it does to just run the store, directly.

Amazon head Jeff Bezos has pushed back against reports that the stores are aimed at reducing the number of jobs in the American retail space to very nearly zero, though it’s unclear precisely how these Go stores would create any jobs to compensate for those they eliminate.

The impact of the technology, if and when it gets up and running, will likely be enormous. Target exec and outspoken Amazon Go skeptic Mike McNamara told Recode, “I’m quite happy for them to take the lead and, if it works, I’m quite happy to copy them.” This will very likely be the attitude all over the industry — their lead in physical stores means they will easily be able to develop and implement their own solution if Go becomes a wild success. And, in any case, some believe physical Go stores could simply be a sales pitch aimed at forcing retailers to license the technology from Amazon.


Inverse has reached out to Amazon and we’ll update this story when we hear back.