Razors, workout clothes, stationery, dog toys, even ingredients for dinner — lately, it seems like anything you might want is available for purchase through a subscription service. Sock Fancy is the first e-commerce subscription business we’ve interviewed, so we were eager to see how things work behind the scenes. As it turns out, the benefits and challenges are certainly unique.

Lifelong friends Stefan Lewinger and Futhum Tewolde started Sock Fancy because they saw an opportunity. Futhum loved wearing fun socks, but he could never find any that were both well-made and affordable. The roommates started their business mere weeks after coming up with the idea. They went from storing their inventory on the ping-pong table in their house to working out of a 5,000-square-foot warehouse!

Obviously, I’m familiar with e-commerce subscriptions, but until talking to Stefan and Futhum, I had no idea how many pros there are to running one! Shipping once a month keeps things predictable, as they always know how much inventory they need. Also, they run their subscription with an “awesomely random” element, so customers don’t get to pick exactly which design they’ll receive. The surprise element keeps things engaging for the customer, and it streamlines the operations side of things.Of course, there are downsides, too. Getting orders out all at once and at the same time each month only gets harder as you grow.

These days, the Sock Fancy team is prepared to handle that volume, but a couple years ago, he found himself drowning in orders. He told me how the back-end of their site crashed multiple times during the 2014 holiday season. This temporarily broke their sock-matching program (they call it the Automagical Sock Matcher), so the random socks weren’t being properly assigned to members’ orders. They ended up having to manually assign SKUs to thousands of orders! Somehow they managed to recover without losing more than a week’s time, but it wasn’t the best way to spend the holiday season.After that, Stefan and Futhum realized they needed to up their shipping and production game pretty quickly. “That included finding high-volume shippers, better printers, hiring more warehouse specialists, building a custom shipping database, and a whole litany of other solutions all in an effort to avoid those big mistakes that could potentially delay shipments for an entire month,” Stefan pointed out.

Honestly, I assumed that a subscription model would make life easier for an e-commerce business, but it sounds like its unique pros come with unique cons, too. But neither Stefan nor Futhum have any regrets about starting Sock Fancy.

Sock Fancy’s socks are fun and comfortable, so it’s no surprise that customers stay subscribed to see what will arrive in their mailbox next.

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