The art of management lies in the capacity to select from the many activities of seemingly comparable significance the one or two or three that provide leverage well beyond the others and concentrate on them. For me, paying close attention to customer complaints constitutes a high-leverage activity.

Aside from making a customer happy, the pursuit tends to produce important insights into the workings of my own operation. Such complaints may be numerous, and though all of them need to be followed up by someone, they don’t all require or wouldn’t all benefit from my personal attention. Which one out of ten or twenty complaints to dig into, analyze, and follow up is where art comes into the work of a manager. The basis of that art is an intuition that behind this complaint and not the other lurk many deeper problems.

— High Output Management by Andrew S. Grove