1) A retailer who is positioned with long term sustained competitive advantage (i.e. Starbucks nationally does have competition from Tim Horton's, McDonald's, Speedway, etc., but it is considered the premium coffee brand with intense distribution who won't find online buying of its primary product a direct threat anytime soon...it's coffee on the go for God's sake).
2) A retailer who is NOT positioned with long term sustained competitive advantage (i.e. Sears is located in physical traditional malls that Credit Swiss predicts 1/4 will be completely closed within 5 years, sells clothing that is not considered fashionable and is easily cannibalized online and elsewhere by Marshalls, etc., as well as appliances that more and more competitors like Best Buy and Home Depot/Lowe's now sell in mass)