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Why are some long term investors so concerned about their entry price?
This is not hypothetical, this is an accurate story. I am a long-term investor. I have a bunch of money that I'd like to invest and I plan on spreading it out over five or six mutual funds and ETFs, roughly according to the Canadian Couch Potato model portfolio (that is, passive mutual funds and ETFs rather than specific stocks). I am concerned that if I invest the full amount and the stock market crashes 30% next month, I will have paid more than I had to. As I am investing for the long term, I expect to more than regain my investment, but I still wouldn't be thrilled with paying 30% more than I had to. Instead, I am investing my money in three stages. I invested the first third earlier this month. I'll invest the next third in a few months, and the final third a few months after that. If the stock market climbs, as I expect is more likely the case, I will have lost out on some potential upside. However, if the stock market crashes next month, I will end up paying a lower average cost as two of my three purchases will occur after the crash. On average, as a long-term investor, I expect the stock market to go up. In the short term, I expect much more fluctuation. Statistically speaking, I'd do better to invest all the money at once as most of the time, the trend is upward. However, I am willing to trade some potential upside for a somewhat reduced risk of downside over the course of the next few months. If we were talking a price difference of 1% as mentioned in the question, I wouldn't care. I expect to see average annual returns far above this. But stock market crashes can cause the loss of 20 to 30% or more, and those are numbers I care about. I'd much rather buy in at 30% less than the current price, after all.