I was checking my daughter's investment account recently, and I realized that I'm kind of an idiot.

I'd forgotten that I'd bought a dozen or so shares of Motley Fool Stock Advisor recommendation Quality Systems (NASDAQ:QSII) for her account. I hadn't been tracking the stock or news surrounding the company. I felt like a real idiot until I checked my cost basis and realized that the investment was up more than 150%.

So maybe we idiots have it right.

Warren Buffett: Idiot
Every day, I hear stock jocks gloat and die with each 10% rise or fall in their stock price. But there's a big difference between stock jocks and master investors: Master investors sacrifice short-term gains to build real wealth.

As the head of Berkshire Hathaway, master investor Warren Buffett has said that he expects to "keep permanently our primary holdings." The man has directed Berkshire to an incredible 40-year compounded annual growth rate of 21.9% by doing all his work on the front end -- identifying superior companies -- and then just forgetting about the prospect of selling.

Buffett has never sold a share of Berkshire Hathaway, and he says his performance would have been even better than 21.9% if he'd never sold a single share of any of his investments. That may sound like an idiot's approach, but those aren't the results of an idiot.

Shelby Davis: Idiot
Shelby Davis turned $50,000 into a fortune greater than $800 million during a lifetime of saving and investing, landing him on the Forbes list of the richest Americans before his death.

Davis is frequently called a B-list money manager, but there's nothing B-list about his returns. Like Buffett, he bought stocks to hold and said before he died that he, too, would have been better off if he had never sold a single investment.

Tom Gardner : Idiot
Well, not really, since he's the one who found Quality Systems in the first place. And if I'd bought when he first recommended the company and not waited, my investment would be up more than 430% -- significantly more than the paltry 150% my daughter has earned. But Tom recently told me that his biggest investing regrets are the companies he's sold over the years.

Tom's sold eight positions from his Stock Advisor portfolio: Hypercom (NYSE:HYC), Daktronics (NASDAQ:DAKT), PossisMedical (NASDAQ:POSS), KenseyNash (NASDAQ:KNSY), Websense (NASDAQ:WBSN), Sanderson Farms (NASDAQ:SAFM), and two positions in Whole Foods. Of those, Kensey Nash, Websense, Sanderson Farms, and Whole Foods are significantly higher than the price at which he sold them. In the case of Websense, the 3% loss Tom realized when he sold would be a 170% gain today. Whoops. His Stock Advisor picks are still smoking the market by a wide margin, but you can imagine his regrets on giving up those eventual winners.

Find superior companies
The key to the buying-and-forgetting approach, of course, is identifying and buying into superior companies with superior performance. That's where Tom -- not to mention his brother/co-founder Dave -- help me.

I read about Quality Systems in Stock Advisor -- our newsletter in which Tom and Dave go head-to-head to find the best stocks anywhere -- and the business made sense to me. As Tom wrote, the company's software helps private-practice physicians automate administrative and diagnostic records. Growing industry. Leader in the field. Smart business approach. Yup, makes sense. So I bought a small chunk and forgot it. That blend of magic and ignorance has turned my investment into a thing of beauty.

Tom and Dave are finding companies like that all the time -- in all, David's picks are up 55% and Tom's are up 58% compared with the S&P's 18% -- and I plan to keep adding them to my daughter's portfolio before letting them slip once again from my consciousness.

To find the companies you might want to buy and forget, give Stock Advisor a whirl. For $149, you'll get two stock recommendations per month, access to all of Tom and Dave's previous picks, and access to the dedicated Stock Advisor discussion boards, where Tom and Dave post regularly and where you'll find armies of like-minded investors sharing wisdom, ideas, and analysis. For a limited time, you'll also receive a free copy of The Motley Fool's brand-new Blue-Chip Report 2005: 10 Monster Stocks for the Next Decade -- a $49 value of 10 great stock ideas that have a place in every portfolio. As always, the Fool's money-back guarantee stands behind the offer. Click here to learn more.

As for Quality Systems, the stock has traded down of late and is about 10% off the all-time high it set at the beginning of June. But I'm not concerned. This is a superior company, and my daughter and I will do well to heed the wisdom of Buffett, Davis, and Tom Gardner and, in the words of Tony Soprano, just "Fuhgeddaboudit."

Roger Friedman is the managing editor of newsletters and the author of Nipple Confusion, Uncoordinated Pooping and Spittle: The Life of a Newborn's Father . He (and his daughter) own shares of Quality Systems. The Motley Fool is investors writing for investors .