Companies and overzealous entrepreneurs have tried to create the “universal shopping cart” since the beginning of ecommerce. The idea is to aggregate all of commerce into a single checkout interface and take a percent of sales as a fee. Dozens of companies have attempted to achieve this, chief among them Spring, the app-turned-website that Shoprunner is acquiring. (The acquisition will likely not make anyone much money, given the company has raised over $100 million.)

Spring is the most recent and press-worthy company striving to become the “universal shopping cart,” but many others came before it, ranging from “new age” department stores to technology platforms and back-end service companies. None of them has ever been realized to the degree promised. It turns out that managing the front-end relationship with customers and the back-end relationship with suppliers is quite challenging at scale. But it’s the front end that’s most crucial to success and usually where consequential oversights occur—the same misdirection that leads to the fallacy of ecommerce’s infinite shelf space.

Amazon is the best current example of the universal cart. You can buy millions of brands with the same account, often on the same site or among Amazon’s sibling sites, and Prime ensures it will show up at your doorstep in a few days or even sooner. Prime, as a bundle, further increases the Amazon cart’s “universal” nature, with the possibility of adding even more services under the same umbrella account. But Amazon is not trying to build a universal shopping cart—its ambitions are much larger: becoming a universal economic system that taxes the economy.

Stripe might be the second-best example, but it’s untraditional. Stripe provides payment infrastructure for digital companies under the slogan, “increase the internet’s GDP.” In exchange for its services, Stripe takes a percentage of all payments it processes, often somewhere around 3% of the transaction. While Stripe is not a universal shopping cart and few consumers interact with it, it’s becoming the universal plumbing for the internet—again, a deeper aspiration than just a universal shopping cart. In doing so, the company also avoids having to manage the consumer relationship and mostly focuses on businesses and the back end.

Instagram, Pinterest and Facebook have also tried or are trying to somehow act as an aggregated layer that commerce would run through, but most of those efforts have gone nowhere, especially given the scale of these platforms.

Shopify comes next, but like Stripe, it exists more on the back end. It’s also a distributed attempt at the universal shopping cart. Hundreds of thousands of merchants use Shopify to host their websites, but few shoppers know about them since the focus is on the brand itself. However, it has started offering shoppers the ability to save their info to use across all Shopify sites, an interesting evolution that moves it close to some type of universal shopping cart.

There is one key to success for Shopify and Stripe: They are not trying to build a consumer-facing brand, which entails getting in the way of the actual brand that would use their services, though they are still used in these front-end interactions—just invisibly. On the other hand, Spring and its ilk try to disintermediate the brand from its shopper, which often backfires. Amazon is somewhere in the middle, and while it frustrates many brands, its sheer size forces many of them to stick with the channel and continue selling on Amazon, even if the brand experience for the customer isn’t great.

Coming full circle, Spring and its mostly dead competitors had a number of problems:

  • It was never clear how these companies would build a critical mass of customers, which is why brands work with department stores and other platforms—because they have the customer base the brands do not.
  • Most of these companies end up looking like department stores with a new coat of paint, rather than the transformative platform that was promised. There are already plenty of department stores with the same products, and no one needs more of them. Creating a differentiated merchandise mix remains difficult in the digital era when most products are widely available.
  • These companies also raised way too much money to warrant a good exit, and the challenges of this specific ecommerce space only makes it harder to recoup anything for investors, founders and employees.
  • As a result of these challenges, Spring turned to discounting products in order to drive its business and user base, effectively playing in a lower tier of the market where shoppers were hunting for bargains. Merchandising and supporting this fickle and ever-changing assortment is not easy, and it’s questionable if the customer base that wants them is worth the effort.

For these reasons, among others, it should be clear that the quest to build a universal shopping cart is likely a futile one. In fact, some of the successful examples mentioned above never sought out to accomplish that in the first place, but rather had more ambitious or adjacent goals. While entrepreneurs will likely continue trying to build these companies, it’s worth asking if a universal shopping cart will ever exist at all. As of now, the answer seems to be a resounding no.