Microsoft's returns as a live sign of a wide moat
The five sources of a durable competitive moat
| Moat Source | How It Works | Examples |
|---|---|---|
| Network effects | Product improves as more people use it | Visa, Google Search, social platforms |
| Switching costs | Too expensive or painful to leave | Enterprise software, banking |
| Cost advantages | Produce at lower cost than anyone | Scale economies, proprietary processes |
| Intangibles | Brands, patents, regulatory licenses | Pharma patents, luxury brands, regulated utilities |
| Efficient scale | Market only supports one profitable player | Railroads, pipelines, utilities |
What Buffett means by an economic moat
Buffett calls durable competitive advantages 'moats.' The wider and deeper the moat, the longer a company can earn returns above its cost of capital.
Reading Visa's returns to gauge how wide a moat is
Why structural advantages beat luck over the long run
Why regulation is the main threat to a dominant company
Going deeper: why monopolies restrict output
Going deeper (optional). Up next: the economist's version of monopoly -- why a firm with pricing power deliberately produces LESS than a competitive market would. An optional aside you can skip on first pass and come back to anytime. Continue when you're curious.
A monopolist faces the entire downward-sloping demand curve. To sell one more unit it usually has to shave the price on EVERY unit it sells, not just the last one -- so the extra revenue that unit brings in (its marginal revenue) comes in BELOW the price on the sticker. Economists write this as MR < P. A perfectly competitive firm is different: it is so small it can sell all it wants at the going market price, so for it marginal revenue simply equals price (MR = P).
Every firm maximizes profit at the same point: where marginal revenue meets marginal cost (MR = MC) -- the same next-unit rule from Marginal Analysis. But because the monopolist's MR sits below its price, that MR = MC point is reached at a LOWER quantity and a HIGHER price than a competitive market would settle at. The units in between -- the trades that would have happened under competition but don't -- are lost value economists call deadweight loss. That destroyed value, not just the high price itself, is why monopoly power draws regulators (the exact risk flagged in the check-in above).
Sit with the ideas.
A payment network processes 65% of all card transactions globally and earns a 55% operating margin consistently for a decade. A competitor launches with lower fees. What protects the incumbent?