Primary vs. Secondary Market
from Buffett's 1992 Letter
Despite the success we experienced with our Gillette preferred, which converted to common stock in 1991, and despite our reasonable results with other negotiated purchases of preferreds, our overall performance with such purchases has been inferior to that we have achieved with purchases made in the secondary market. This is actually the result we expected. It corresponds with our belief that an intelligent investor in common stocks will do better in the secondary market than he will do buying new issues.
The reason has to do with the way prices are set in each instance. The secondary market, which is periodically ruled by mass folly, is constantly setting a "clearing" price. No matter how foolish that price may be, it's what counts for the holder of a stock or bond who needs or wishes to sell, of whom there are always going to be a few at any moment. In many instances, shares worth x in business value have sold in the market for 1/2x or less.
The new-issue market, on the other hand, is ruled by controlling stockholders and corporations, who can usually select the timing of offerings or, if the market looks unfavorable, can avoid an offering altogether. Understandably, these sellers are not going to offer any bargains, either by way of a public offering or in a negotiated transaction: It's rare you'll find x for 1/2x here. Indeed, in the case of common-stock offerings, selling shareholders are often motivated to unload only when they feel the market is overpaying. (These sellers, of course, would state that proposition somewhat differently, averring instead that they simply resist selling when the market is underpaying for their goods.)