Suppliers are scrambling to meet Walmart’s tighter standards for delivery performance — and they can expect the giant retailer to keep raising the bar.

In an increasingly competitive industry, retailers can no longer rely on providing the right product at the right price, with customer service taking center ground in the battle for consumers’ hard-earned cash.

The growing popularity of the urban lifestyle is making new demands on e-tailers – and raising the possibility of gridlock for logistics providers.