Not Dumping the Losers

“…an example of laziness is not dumping the losers. I recall that when I was a young sprig, I read about the Dow Theory of investing or maybe a commentary about it. The simple rules included the admonition to cut losses and let your gains run. I used to do that scrupulously, but as old age and superstition have overtaken me I often leave losers and carcasses on my statements. Maybe part of the reason is the few minutes of work it would take to learn the cost basis and then the shattering realization of how huge my capital losses were. (Yes, I was suckered into buying Internet stocks, too. Luckily, in fairly small numbers, or I would be writing this from a padded cell.) When a stock has been a loser for a long time, say sayonara, in the words of Marlon Brando, even if it takes a bit of work to do it.”
Ben Stein
New York Times