Which model do you think would be the toughest to operate? Why? What would be an example of an existing retailer using this model?

\\begin{tabular}{|c|c|c|} \\hline Brick \\& Mortar & E-commerce & Omnichannel \\\\ \\hline Direct-to-Consumer & Subscription & Marketplace \\\\ \\hline Pop-up & Franchise & Off-price \\\\ \\hline Collaborative & Social Commerce & Private Label \\\\ \\hline Click \\& Collect & Luxury & Consignment \\\\ \\hline \\end{tabular}