If you understood a business perfectly and the future of the business, you would need very little in the way of a margin of safety. So, the more vulnerable the business is, assuming you still want to invest in it, the larger margin of safety you'd need. If you're driving a truck across a bridge that says it holds 10,000 pounds and you've got a 9,800 pound vehicle, if the bridge is 6 inches above the crevice it covers, you may feel okay, but if it's over the Grand Canyon, you may feel you want a little larger margin of safety.
I make no effort to predict the course of general business or the stock market. Period. However, currently there are practices snowballing in the security markets and business world which, while devoid of short term predictive value, bother me as to possible long term consequences.
The financial calculus that Charlie and I employ would never permit our trading a good night's sleep for a shot at a few extra percentage points of return. I've never believed in risking what my friends and family have and need in order to pursue what they don't have and don't need.
There are a few investment managers, of course, who are very good - though in the short run, it's difficult to determine whether a great record is due to luck or talent. Most advisors, however, are far better at generating high fees than they are at generating high returns. In truth, their core competence is salesmanship. Rather than listen to their siren songs, investors - large and small - should instead read Jack Bogle's The Little Book of Common Sense Investing.
The best business returns are usually achieved by companies that are doing something quite similar today to what they were doing five or ten years ago.
We say we are trying to buy into businesses with excellent economics, run by honest and able people at a decent price. We buy very few securities, so we look at it as "focused" investing.
Asset-heavy businesses generally earn low rates of return - rates that often barely provide enough capital to fund the inflationary needs of the existing business, with nothing left over for real growth, for distribution to owners, or for acquisition of new businesses
SUPPOSE that an investor you admire and trust comes to you with an investment idea. This is a good one, he says enthusiastically. I'm in it, and I think you should be, too.
A diamond cannot be polished without friction, nor a person perfected without trials. Someone is enjoying shade today because someone planted a tree a long time ago.