FrameworkLessonInvestingPsychology and behaviourCareers
A handful of outcomes carries a portfolio, and a career
Morgan Housel · The Psychology of Money
The idea
Housel's chapter on tails makes a point most people accept in theory and ignore in practice: in any portfolio, most positions do roughly nothing and a few do almost everything. The same is true of a venture fund's returns, of an index's long-run gains, and of a career, where a small number of decisions and relationships produce most of what happens. If that is the shape of the world, the right response is to stay in the game long enough to be present for the tail, and to avoid any single loss that removes you from it. Most investing mistakes are failures of staying power rather than of analysis.
Results come from a few outcomes, so the job is to survive long enough to be there when they arrive.
When it works
Position sizing, venture portfolio construction, and any moment of frustration that most of your effort seems to produce nothing.
When it may fail
The tail argument can excuse holding losers forever. The venture version works because losses are capped at the investment; in a leveraged book they are not.
How to use it
Look at any fund's return attribution. Count how many positions produced three quarters of the gain. Then ask what the fund did to stay solvent through the positions that did nothing.
Where it came from
Book The Psychology of Money · Morgan Housel
What the source says. Why sensible people do unsensible things with money, and a chapter on how a few outcomes carry an entire portfolio that is worth the book on its own.
Competing perspectives
Argues against
The cost of protection, itemised: what a seven-year hedge actually costA hedge is a premium paid every year; over a long bull market the premium is the whole story, so account for it as a cost from the start.
Connected ideas
Says something similar
Compounding needs an uninterrupted run more than it needs a good yearDuration beats brilliance in compounding; arrange your life and portfolio so you are never forced to stop.
Supports
Traders who agree on nothing else all agree about risk controlThe common factor among people who last is not how they pick trades but how they limit what a wrong one costs.
Concepts
Put it to work on L3VLUP
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