Many of the retailers who rounded out the bottom of the list are at a natural disadvantage because of their business models.
The grocery industry, in particular, operates on traditionally low margins, which can make it difficult to pour money into building out a comprehensive online strategy. Grocery sales are also underpenetrated on the Web compared to other areas, such as apparel, making it less of a priority, Galloway said.
Off-price stores such as T.J. Maxx face their own set of challenges, because their products are priced so low that shipping costs are more prohibitive. On Ross Stores' most recent earnings call, the company's president reiterated that it has no plans to operate an e-commerce business, because it doesn't seem economical for a retailer whose average unit price is $10.
On the flip side, struggling department stores J.C. Penney, Sears and Kmart all earned "gifted" rankings. L2 called out Sears' early adoption of the ship-from-store capability, which many other retailers are just now adopting. Kmart led the index for the most YouTube channel views, while Penney's earned kudos for its mobile-optimized site and customer service-oriented tweets.
Despite these companies' high rankings, Galloway emphasized that they can't rely on a digital strategy alone to boost their business.
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"Digital is a fantastic tool but it's not a strategy in and among itself," he said.