It’s interesting to see online success stories, like Warby Parker and Bonobos, opening real world stores, and reversing the traditional retail trajectory. We’re often asked if online players face hurdles operating in the brick-and-mortar world and the answer is yes, but not for the reasons you’d think.

In fact, the main part of our business—inventory planning—is quite similar. The big difference between e-commerce and physical stores are the sales tools.

In the online world, your sales people are your online marketers, and to a large extent your search functionality. The online marketers get customers to your site, and the search tool helps them find products to buy. In the brick-and-mortar world the sales instruments are your staff.

So, say a customer comes to your site looking for a purple sweater. If you don’t have a purple sweater in their size, they may start immediately searching elsewhere. If the same thing happens in a physical store the salesperson may suggest something else for the customer to try on and the shopper could have a “I never thought of that!” moment. Online retailers are not good at the “I never thought of that!” experience. Smart online algorithms may suggest similar items, but probably not something outside of the search criteria that would just look good on the shopper. This is one of the advantages of the physical retail world that e-commerce will have trouble replicating.

The in-person experience is also the hardest part for online retailers switching to brick-and-mortar to get right. When it comes to great products, and creating a relatable brand and experience, most online operators have already figured it out before they expand offline. That’s why an integral part of planning that goes into opening a new physical store should be sales strategy and training. In the online world, convenience is your top weapon, but in the offline world you’re adding the advantages of personal interactions, and the ability to touch, feel and try on products immediately.

Given these pros, it’s no wonder that strong e-commerce players want to bring the advantages of brick-and-mortar shopping to customers. They just need to know how to do it right.