In a survey of 10,000 employees from the 1,000 largest companies, 40% of workers cited "lack of recognition" as a key reason for leaving a job. This thank-you scarcity is, just as important, a tragedy for your customers. Because when a customer says thanks, they make you happy, but they make themselves even happier. A thank-you from a customer, then, creates a radiating halo of happiness -- employees feel recognized, customers feel joyful, and there's less coughing. Suppose there were some way to lower the transaction costs of a thank-you so much that praise became effortless. American Airlines has taken a step in the right direction with a program called Applause. It gives frequent travelers who've reached "elite" status a set of preprinted cards that can be handed to employees who provide exemplary service. Companies should pave the way to praise. If it works well enough, maybe someday people will see call centers that receive as many thank-yous as complaints.