19 things keeping you from getting rich, according to a journalist who spent his career studying millionaires

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Journalist Napoleon Hill set out to uncover the key to wealth around 80 years ago. He studied more than 500 self-made millionaires over a span of 20 years, and his research culminated in what would become a timeless personal-finance classic: "Think and Grow Rich."

In addition to boiling down the "secret" to building wealth in his book, he revealed 30 "major causes of failure" that hold many of us back from getting rich.

Here are 19 that are still relevant today:

Not having a well-defined purpose

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"There is no hope of success for the person who does not have a central purpose, or definite goal, at which to aim," Hill writes.

If you're looking to build wealth, start with visualizing a savings goal with a specific price tag. Then form a financial plan and determine exactly where you want your money to go.

Lack of ambition

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You have to want to aim above mediocrity, Hill says: "We offer no hope for the person who is so indifferent as not to want to get ahead in life, and who is not willing to pay the price."

Wealth doesn't simply appear. You have to work toward it with patience and persistence. A good starting point is to invest your money — the earlier the better — and let the power of compound interest build your wealth. It doesn't take much time or effort, but it does require action on your part.

Not properly applying your education

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A college degree alone won't cut it. Knowledge is only potential power, and it will not become useful or lead to great wealth unless it is organized and applied to life, Hill emphasizes:

Education consists not so much of knowledge, but of knowledge effectively and persistently applied. Men are paid not merely for what they know, but more particularly for what they do with that which they know.

Make it a priority to constantly learn new things and challenge your mind. There's a reason that many of today's successful and wealthy people are voracious readers.

See the rest of the story at Business Insider