When it comes to shopping and buying, the Millennial generation appears to play by its own rules. And businesses that fail to understand the Millennial mindset are destined to fall behind their competition – and perhaps plummet into irrelevancy, says Gui Costin, an entrepreneur, consultant and author of Millennials Are Not Aliens. “Millennials are changing how we buy, how we sell, how we vacation, how we invest, and just about everything else,” Costin says. “If you’re running a business, you have to pay attention to how they think and act.” Millennials grew up under very different circumstances than Baby Boomers and Generation X, though, and the way in which they came of age greatly influenced them. One example is their relationship with technology. Costin says there’s plenty that businesses need to understand about Millennials, but here are just a few other facts about their consumer habits worth paying attention to:

They let everyone know about their buying experiences. It is not uncommon for Millennials to candidly share details about their buying experiences, good or bad, on their public social media platforms. “This can translate to bad news for businesses that underperform or, conversely, great news for those that exceed expectations,” Costin says.

Big purchases can happen virtually. For many older people, it’s difficult to even conceive the idea of buying a car, for example, without ever physically seeing or touching it first. “Millennials do it all the time,” Costin says. “In fact, they are the very first of all the generations to make a large purchase without first performing an on-site inspection.”

Brand loyalty means something. No matter how fickle many people believe Millennials to be, they are extremely brand loyal, Costin says. In fact,60 percent of Millennials say they almost always stick to brands they currently purchase.

Information is essential. Millennials scour the internet to learn about a brand or product before making a purchase. They check websites, blogs, or peer reviews that they trust.

Instant gratification is paramount. Because they have grown up in a digital age, Millennials are used to speed and immediate gratification. “They value prompt feedback and communication and do not like wasting time,” Costin says. “Think emails, text messages, and online messaging.”

Gui Costin (www.guicostin.com), author of Millennials Are Not Aliens, is an entrepreneur, and founder of Dakota, a company that sells and markets institutional investment strategies.