The hottest menu strategy: never-ending limited-time offers The McDonald's McRib is among the most iconic limited-time offers, and its return has become an annual celebration for its fans. STEPHANE JOURDAIN/AFP via Getty Images In the attention economy, restaurants sell urgency through an endless series of limited-time offers. The promotions are becoming hyper-personalized, but consumers' attention is increasingly split. While LTOs drive sales, endless promos risk training customers to only engage when there's a deal. The offer may expire at midnight, but the strategy sure won't. For restaurant chains chasing attention in an increasingly fractured landscape, the limited-time offer — once a seasonal gimmick — is now a permanent menu fixture.…