7 Massively Overhyped Careers to AvoidOpportunists beware.

Ever since social media and smartphones captured the imagination of a billion people, we've seen a rash of new career fields that never existed before. Many of you, no doubt, have jumped on these opportunities with fad-like fervor. And therein lies the rub. You're far from alone.

These fields are now flooded. The problem, as many have already learned, is that if it's easy – if the barriers and costs to entry are low – then anyone can do it. And that's exactly what's happening. Not just anyone, but anyone and everyone. And that means heavy competition, no pricing power, slim profit margins and low income.

If all it takes is some online classes, a certificate, a seminar, a self-help book and a website to proclaim that you're the best darn, award-winning, best-selling, guru, expert, or whatever, you can bet that a flood of other people with no real marketable skill or expertise will go for it. And they have.

And when it comes to fads, you can always count on one thing: they will come, and they will go. Granted, fads may gain viral traction in the blink of an eye, but once people discover that there's nothing to them – that they really are all hype – they vanish just as quickly as they appeared.

Related:10 Behaviors of Genuinely Successful People

Don't get me wrong. There are legitimate experts in every field, even some of these, but if you're not a top performer, you might want to reconsider your future in these faddish gigs.

1. Professional coaching

There are coaches for everything: leadership, strengths, performance, career, fitness, family, holistic, happiness and, of course, life. There are even coaches who coach people on becoming coaches. And no, I'm not making that up. The vast majority have three things in common: a worthless certificate, no real expertise and a lousy business.

2. Emotional intelligence consulting

There is no scientific correlation between emotional quotient and job success. If emotional intelligence was a requirement for business leadership, then Bill Gates, Steve Jobs, Mark Zuckerberg, Larry Page, Mark Cuban and Donald Trump would never have made it big. Besides, the emotional intelligence testis so easy to game, it isn't funny.

3. Working in the gig economy

Driving an Uber cab, renting out a room on Airbnb, selling used stuff on eBay or generating online content for peanuts are definitely not high-paying gigs. While the self-employed make up 17 percent of the U.S. workforce, they generate just 7 percent of the nation's gross domestic product. This is why we have a productivity crisis in America -- we have a growing slacker economy.

4. Millennial consulting

Maybe Millennials are self-centered and entitled. So was I at that age. Then something happened. I grew up. At some point, everyone will wake up and realize that young people are childish and egocentric. Then they mature. Besides, with median employee ages between 28 and 30, Google, Facebook, LinkedIn and Salesforce don't seem to be having much trouble getting their Millennials to perform.

Related:Want Big Things Out of Life? Expect Big Things of Yourself.

5. Employee engagement consulting

Gallup has done a marvelous job turninguseless employee surveysinto a checkbox for every HR executive. In reality, employee engagement is just employee satisfaction 2.0. The most successful companies on earth don't need employee engagement consultants to create cultures where their most valuable assets, their people, thrive.

6. Self-publishing

Everyone and his brother claims to be a best-selling author these days. I don't care if you were number 499 for a few nanoseconds in some narrow category of an esoteric list, if your Amazon best-seller rank is over 1,000,000 you are not a best-selling author. Published authors can get away with self-publishing. Amateurs can't.

7. Content marketing

The web is so flooded with blogs, posts, tweets, shares and videos that the return on investment for social media and content marketing is practically negligible. And having tons of followers on Twitter or LinkedIn rarely translates into meaningful results for most businesses. Don't even get me started on personal branding gurus.

If you want to achieve great things in life, loving your work is not enough. Working long hours is not enough. What you do also has to be marketable. All the passion and inspiration in the world will not overcome the laws of supply and demand. If it's easy and everyone's doing it, your chances of getting anywhere are somewhere between slim and none.

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