As shoppers grow more comfortable browsing and making purchases online—and in particular, on their mobile devices—retailers with an exhaustive digital strategy will be the big winners, PwC's Barr said.
According to a new report by IBM's Digital Analytics Benchmark, mobile sales accounted for 22.6 percent of online revenues and 45 percent of online traffic in the November and December period, and their adoption continues to rise. As of March, mobile traffic to U.S. retail sites hit 47.4 percent, with mobile sales reaching 24.4 percent.
The rapid increase in mobile penetration caused a number of retailers to stumble last holiday, most notably Best Buy. While there will still be some laggards, Sides said he expects companies will be better prepared for the shift. He added that a properly functioning website can be critical for retailers, as online shoppers have a much shorter attention span than those who took the time to drive out to a physical store.
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At the time of Best Buy's failure last year, ChannelAdvisor estimated a retailer could lose about 8 percent of the day's online sales each hour that it's down.
"If you have a failure either via mobile app or website, folks move to the next option," Sides said.
Sides also expects to see a continuation of the bifurcation that retailers experienced last season—where high-end and discount retailers perform well but those positioned toward middle-income shoppers continue to get squeezed.
Along those lines, a report released by Moody's on Tuesday said that the off-price segment will continue to outperform the broader home and apparel categories for "at least the next five years."
For Beemer, the winners will be those retailers who don't give away the store with 60 percent discounts.
"I don't know how many more promotions we can run," he said. "When you start selling items [for] that much less … it's pretty hard to make up for it."