A long held, but incorrect, view is that all people are always motivated by money. We see this put into practice by ‘rewarding’ employees with small bonuses, t-shirts, meals, and the ever popular—gift cards. Many years ago, we heard a fast-rising leader mention that monetary tokens are inherently flawed; managers can only dole them out while there is money in the coffers. Put simply, gift cards are not sustainable. Instead, he urged us to consider writing short, but personal, hand-written thank-you cards.

This intuitive and wildly successful leader has some backing. Renowned organizational theorist and psychologist, Frederick Herzberg came up with the Motivator-Hygiene model to explain how handwritten thank-you notes could actually trump $50 Wal-Mart gift cards. He said that pay, trinkets, or a big office are Hygiene factors. When doled out, they can never lead to job satisfaction. Rather, not having them can lead to job dissatisfaction. Conversely, Herzberg suggested that leaders inspire when they market in non-financial tools, what he called motivational factors. These motivational factors involve job recognition, personal feedback, and opportunities for growth.

Taking five minutes each month to write two thank-you notes does just that. It is a personal way to provide job recognition and a sense of achievement. Maybe most importantly, they can be sustained over time—whether business is good or bad. Where $50 gift cards cannot survive a dip in the economy, handwritten thank-you notes are completely sustainable.

Show that you care enough to pull out the old pen and paper. You’ll be surprised how long your employees will keep that handwritten note. Everyone does gift cards these days. They’re cheap but expensive. Try thank-you cards. They are immensely valuable but inexpensive.