Sometimes a childlike (or actual child's) innocence means more than all the numbers, charts, and studying in the world. That's not to say you should always go with your gut -- certainly, don't do that -- but there are lessons to be learned from how a kid thinks.
It's not easy to pick a stock portfolio that will beat the market average: most mutual fund managers don't, and they're supposed to be pros. But using Motley Fool CAPS, anyone can try their hand at stock picking, and get ranked over time based on how well they do. One early CAPS stock picker -- he began when he was 8, back in 2007 -- was Motley Fool co-founder David Gardner's son Zack.
In this segment of the Rule Breaker Investing podcast, Zack is his dad's special guest, and they review his hits, his misses, and why he chose the stocks he did. He's been on both sides of the Google/Alphabet (GOOG 0.66%) (GOOGL 0.49%) bet, but he's always been bullish on Starbucks (SBUX -0.40%), based on their baked goods.

A transcript follows the video.

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This podcast was recorded on July 5, 2016.

David Gardner: Your next pick was Google, and I want to read for you what you said at the time. This was Jan. 23, 2007. And by the way, you had a red thumb on Google, so you were picking it to lose to the market back in January 2007. You wrote simply, "Google (and then all caps) STINKS. (All caps) BOO, GOOGLE." How much time did you really put into the thinking?

Zack Gardner: That's like I saw it at eight years of consideration right there.

David: [Laughs]

Zack: Really, it was the consummation of my life to that point. It was just all put into that pitch.

David: I'm assuming you don't remember this (I don't either), but you closed that pick out eight days later. Google had gone up 5%, the market had gone up about 1%, so you were four points underwater there, and you closed it out.

Zack: I have no regrets there.

David: And today, Zack, I note that on this same scorecard (which is on CAPS at SweetZ64, which is your CAPS page), you have Google long. In September 2012 you had a change of heart. You wrote, "While it may be one of the single, safest buys ever, it's still a welcome addition to my portfolio," making it sound as if safety was not what you're shooting for.

Zack: Probably not if you look across some of my picks. Highly volatile, but I figure [you should] get something safe in there, because there's nothing wrong with that.

David: And we're going to get to a few of those, but I will say Google is up 97% since you picked it. The stock market is up 42%. That one's worked out well. Not all of them, by the way, have worked out well...

Zack: [Laughs]

David: ...we'll get to those in a little while. So let me just go over a few other funny highlights. You picked Starbucks on Jan. 11, 2007, so just about 10 days after you started. You wrote at the time, "Really good company. My dad takes me there a lot. We go to it a lot. It has the best madeleines in the world," and then all caps, "YUMMY!" I know you still like Starbucks' madeleines.

Zack: I stand behind those words, even right now.

David: It is a timeless stock and a timeless product. What was funny is that one day later -- because people can comment on CAPS, just like you can comment on Facebook or today -- a comment came in. I never read it to you at the time, because I thought it would make you feel bad. This clearly came from an adult. He didn't know that an 8-year-old kid was who he was talking to.

He wrote, "Yeah, what a great reason to recommend a stock. Thank goodness there's people like this investing, or else the efficient market hypothesis would be true and there'd be no money to be made."

Zack: [Laughs]

David: That's what he wrote a day after. His screen name, for the record: EB38. I don't know if he's still active around And that's not the only comment. There was one other comment made -- this one in September 2011.

This person said, "Most people invest like this, and most people should. Never change, young man. Don't let these FOOLS corrupt you!"

Zack: [Laughs]

David: So now to review your very controversial Starbucks pick with your thinking at the time. Highly criticized by somebody. He was calling out the efficient markets theory (or hypothesis, if you like). And Starbucks picked at $16.35 that day. Today it's, mid-June, clocking in around $55. It's up about 240% and the stock market is up about 55%. You probably hadn't checked back on that or seen that lately, but that ended up being a great pick. Do you have any reflection about that? What can we learn from that moment?

Zack: Pick stocks that matter to you. Although I probably wasn't qualified to be picking anything at 8 years old, just picking [a stock] where you know what you love about it and you know why it's valuable, or why it could be valuable in the future, is just a great thing. It's a solid investing strategy, as our second commenter said.

David: Yes. And the longtime great investor Peter Lynch, of Fidelity Magellan fame, wrote a number of fine investment books, and one of them talked about how he went to a Boston elementary school, I think, and worked with the kids there in an investment club, and they crushed the market. They crushed the market. That's, of course, a great headline and a story at the time when Lynch's book came out, but it's kind of the same thing. Keeping it simple. There's something excellent when you don't try to be too fancy and you don't try to out-think the market. You just go with things that you like.