NEW YORK (TheStreet) -- A Labor Day weekend fishing trip was a reminder to me that there are a lot of similarities between fishing and investing -- and that lessons learned in fishing have application in investing.My son and I set out early Saturday morning on an 85-foot party boat with the hope of catching enough fluke to provide dinner for six that evening. It was indeed a great day for fishing, and the fluke and flounder were abundant. That's certainly not always the case. 1. But while we caught about 25 fish -- plenty of action -- there were just two keepers in the lot. Investment Lesson: You have to be selective about the names in your portfolio. In our case, the law prevented us from keeping more of the flatfish we caught; there is a minimum size of 17 1/2 inches. In my case, I can't own every available net/net, or stock that's trading below net current asset value, nor would I want to. They come in different shapes, different sizes and different qualities, just like fish. 2. Patience is necessary. Without it, no fish. Investment Lesson: When it comes to investing, you need to allow ample time for your investment ideas to play out. You've done your homework and taken a position, and you often have to wait, especially when you are a value investor as I am. In fishing for fluke, you need to wait for the flatties, which are resting on the bottom, to grab your hook. They are not as aggressive as bluefish, and you can't yank your line up every 30 seconds because you're frustrated that there have not been any hits. You've got to let it sit, at least for a while. I've made plenty of mistakes selling names too early. Since we are using the fishing analogy, I made a huge mistake with Cabelas ( CAB), taking a position when it seemed that few understood the potential value, and the stock was in the mid $5 range. It ran into the teens, and I wrote some covered calls, and had the stock taken away at $20. A nice gain, maybe, but Cabela's is now pushing $50.
3. Even though we were fishing primarily for fluke, there were plenty of other hungry sea creatures that grabbed the bait. Many of these put up a much better fight than the fluke. I hooked something that seemed very large and heavy, and it put up a nice fight. I was hoping it was a 30-inch fluke, a real doormat, and enough to feed all of us dinner. Unfortunately, it was actually a 2 1/2-foot sand shark. Investment Lesson: If it seems too good to be true, it probably is. Facebook ( FB) seems to be the poster child for many investment lessons these days, and I'll invoke its name one more time here. I was very hopeful that the sand shark on my line was a huge fluke. But it fought much harder than a fluke would have. That did not diminish my false hope, until I could actually see the fish. Facebook came with much promise, but it was overhyped. Some did not want to believe that it simply was not worth $100 billion. 4. Sometimes, after you've waited for a while and it seems as though nothing is happening, it's time to pull up your line. Perhaps your bait has been taken. Or in some cases we experienced Saturday, there was already a small fish on the hook. It was just too small to get noticed. Either way, it's time to begin again. Investment Lesson: Too much patience is not a good thing either. Sometimes you need to close positions, especially if your original reasons for buying are not playing out. I closed my Wendy's ( WEN) position after a few years of waiting for cost cutting to kick in and for a slick advertising campaign and new product offerings to reinvigorate the brand with consumers. It has not played out that way so far, and I've moved on. Those small fish I mentioned, already on your hook despite the fact that you don't notice them, represent an opportunity cost; you can't catch a bigger fish if you've already hooked a smaller one. That's how I came to view Wendy's; owning it became an opportunity cost of owning something better. The good news was that, though there were only two keepers, it was enough fish for dinner. At the time of publication, the author had no positions in any of the stocks mentioned. This article is commentary by an independent contributor, separate from TheStreet's regular news coverage.