Remember the "Millionaire Next Door"? He was that thrifty dry cleaner or welder who drove an old pickup truck, wore a Timex and bought suits off the rack (if he bought them at all). He scrimped, saved and invested his way to $1 million.
It was a quaint portrait—and a great book in the 1990s. But by the 2000s, the giant green tide of megawealth, filled with super-earners and super-spenders, transformed the world of millionaires. Saving your way to $1 million was still possible, but it wasn't considered wealthy.
Now a new study suggests that the concept of the "Millionaire Next Door" may be coming back in vogue—at least psychologically.
A study from PNC Wealth Management asked people worth $5 million or more in investible assets about the "actions that have most contributed to their financial success."
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The No. 1 response? It wasn't income. It was "saving early and regularly." The second most common response was "making smart investment choices." In a distant third was "earning a lot of money." Ranked fourth was "controlling spending."
When asked to rank the greatest influences on their success, 63 percent said "hard work." That was followed by "good decisions" (16 percent). Only 9 percent said "luck" was the top influence on their success.
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"Most of the millionaires surveyed have controlled their own destiny by working hard and saving early and regularly," said Joseph Jennings, director of investments for PNC Wealth Management. "These are personal choices over which we all have control. This indicates that the 'American dream' is still very much alive."
Of course, every survey done by a financial institution should be taken with a grain of salt. Wealth management firms tend to promote the image of hard-working, heavy savers and investors among their clients. And clients sometimes say the right things in surveys, but act very differently in reality.
As the author Michael Lewis said in his now famous Princeton commencement speech, "if you have had success, you have also had luck—and with luck comes obligation."
But the PNC survey also shows some surprising changes among the millionaires over the past decade. In short, they are moving away from a focus on "quantity of life" and more toward "quality of life."
When asked about what drives their daily decisions, 25 percent of the multimillionaires said "enjoying life more." That's up from only 9 percent, 10 years ago.
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Today, only 8 percent said "feeling a sense of accomplishment" was important—way down from 20 percent a decade ago. And those citing "a more healthful life" tripled over the past 10 years.
And "wealth preservation" was cited three times as much as "wealth accumulation."
Perhaps there is such a thing as "enough" for today's wealthy.
—By CNBC's Robert Frank. Follow him on Twitter @robtfrank.