Action Alerts Plus portfolio manager and TheStreet's founder Jim Cramer has learned a lot over his 30+ years of investing. So he created a list of 25 Rules for Investing that can help you avoid the novice pitfalls that even he fell into on occasion.

Like forgetting that things change.

"Markets change...

Competitors start new price wars to win share...

Companies execute poorly...

Customers cancel orders...

Events happen that make buying decisions more difficult or postpone them."

Rule 18: Be Flexible

"The most important rule of all is: Be flexible," says Cramer. 

"You have to be flexible because business, by nature, is dynamic, not static."

So listen to Cramer talk about why "our buy-and-hold brainwashing totally precludes many of us" from flexible.

Watch Rule #18 now! 

 

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