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 giving up on a stock because it's not working at the moment. 

Rule 20: Giving Up on Value Is a Sin

"Patience is a virtue - giving up on value is a sin," says Cramer.

I see so many people throwing in the towel on companies that have real assets and real worth just because they aren't working now and it angers me."

He recalls a interview he did with Apple's (APPL)  CEO Tim Cook when his stock had fallen from $136 to $93.

Listen in to Rule #20 as he talks about why he held on. 


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