3. Millennials won't settle for less; they want less. There's been a lot made of this unconventional approach of millennials as a sign that their ideals are different than past generations—in particular, a wariness if not outright rejection of Wall Street.
"Millennials are just skeptical of everything as a whole," Financial Finesse's Carter said.
Remember the 1960s? Well, many social researchers studying the 18- to 34-year-old demographic today could look back at that decade and conclude some of its societal skepticism is consistent with that of millennials.
"If you had forecast behaviors of that generation, you probably would have been surprised to find it's the same demographic that was responsible for engineering the 2008 credit crisis," HighTower's Weissbluth said.
Current behaviors aren't a perfect indicator of expected behaviors—they may or may not be consistent with an individual's current outlook.
New message to millennials: No one wants to become their parents, but that does't mean the "you" at 25 is going to be the "you" at 48. You need to outsmart Wall Street, and that doesn't require joining it or rejecting financial intelligence.
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4. Infinite iPad investing. One method millennials have used to reject Wall Street is online investing platforms that require no interaction with a human advisor. The "digital native" phenomenon—those born with a computer in their hands—is real and is a secular shift.
"Millennials absolutely interact with technology in a fundamentally different way than boomers and Gen Xers," Weissbluth said. "They really are the first generation of digital natives."
Online financial-planning firms now offer algorithmic-based programs that make investing in low-cost exchange-traded funds easier than ever before. This is a good development for millennials as a way to get started—with low investment account balances, it's unlikely they would get the full attention of human advisors, anyway. But that doesn't mean when millennials get married and buy a house and have kids, their financial situation won't get more complicated and benefit from a sit-down with an advisor.