In investing, the biggest mistakes are mistakes of
ommision rather than mistakes of commission. There are opportunities
that could be billion dollar mistakes, but they don't show up on the
accounting report. Buying airlines is a risky business. It may be an
attractive security in a flawed business. You might like the terms even
though you don't like the business, and that can be a mistake.
It is better to learn from other people's mistakes as often as possible. But you shouldn't look back too much. You can only live life forward. You can live from your mistakes, but you will do a lot better to stick with things that you know and understand. There has got to be a reason that you decide to buy something. Not because the volume looks good on the chart.
Buffett doesn't think about the macro stuff. You have to focus on what is knowable. A lot of the macro stuff is unknowable. He has never bought a business because of any macro view. You don't want to pass up something intelligent based on some view of what the economy will do. A lot of what Greenspan and people like that say is just nonsense.
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