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Explain It Out LoudStart here

A four-sentence template that fits every instrument on this site, twelve products written out in it, and a drill for finding the one sentence you cannot yet say.

Why out loud. Reading about an instrument and being able to explain it are different skills, and only one of them is tested — in an interview, on a desk, or by a friend who asks what you actually do. The gap is always in the same place: the sentence you skip when reading is the sentence you cannot say. This page is a way of finding it. Education only; nothing here is advice.

The template

  • Sentence 1 — who wants what. Every instrument exists because two parties wanted opposite things badly enough to write it down. Name both of them.
  • Sentence 2 — what the contract obliges, and when. Not the payoff diagram: the obligation. Who must do what, on what date, whether or not they want to by then.
  • Sentence 3 — where the money comes from. Coupon, dividend, spread, premium, the difference between two prices, a fee charged by somebody in the middle. If you cannot name the source, you have described a hope rather than an instrument.
  • Sentence 4 — what makes it lose. The ordinary way, not the dramatic one. Most products lose money through their dullest mechanism.
The test of a good four sentences: somebody who has never heard of the product could, after hearing them, correctly guess who is on the other side and roughly when the loss would show up. If they cannot, one of the four is missing.

Twelve, written out

Common stock

  • A company wants money it never has to repay; an investor wants a share of whatever the business is worth in future.
  • The company owes the shareholder nothing at all — no interest, no repayment date, and no promise of a dividend — beyond a vote and a claim on whatever is left after everybody else has been paid.
  • The money comes from the company's future profits, distributed as dividends or retained and reflected in the price somebody else will pay.
  • It loses when those future profits turn out smaller than the price assumed, and it loses everything when the company fails, because “what is left over” is usually nothing. Full page · plainer still

Government bond

  • A government wants to spend before it has collected the tax; a saver wants a known amount of money on a known date.
  • The government is obliged to pay a fixed coupon on fixed dates and the face amount at maturity, regardless of what has happened to it in between.
  • The money comes from the coupon, plus the difference between what you paid and what you get back.
  • It loses in real terms when inflation outruns the coupon, and it loses in price terms when market yields rise — a fixed payment is worth less once better-paying alternatives exist. Full page

Corporate bond

  • A company wants to borrow at a lower cost than a bank charges; a lender wants more than a government pays and is prepared to look at a balance sheet for it.
  • The company is obliged to the same fixed schedule as a government — with the difference that it can run out of money, and the obligation then goes into a queue.
  • The money comes from the coupon, which contains both the rate a government would pay and a spread for the risk that this issuer will not.
  • It loses in two separate ways that can happen at once: rates rise, or the market decides the spread was too thin. Full page · the spread part

Equity option (a call)

  • A buyer wants exposure to an upward move without committing the full price; a seller wants to be paid now for accepting the obligation to deliver later.
  • The buyer may buy the underlying at the strike until expiry and can walk away; the seller has no such choice — if the buyer exercises, the seller must deliver, at whatever the market price then is.
  • The buyer's money comes from the underlying rising past the strike by more than the premium paid; the seller's comes from the premium, and that is all they will ever make.
  • The buyer loses to time and to falling volatility even when the direction was right — which is why an option can lose on a day the underlying rose. Full page · plain-words version

Interest rate swap

  • One party has a floating-rate obligation and wants certainty; another wants the opposite, or is being paid to take the other side.
  • For an agreed term, one side pays a fixed rate on a notional amount and the other pays a floating rate on the same notional — the notional itself never changes hands.
  • The money is the net difference on each payment date, which is small relative to the notional and is why the notional is a bad measure of the risk.
  • It loses when rates move against your side, and the loss is amplified by the term: a ten-year swap moves several times as much per basis point as a two-year one. Full page · how much, per basis point

Repo

  • One party has securities and needs cash overnight; another has cash and wants it back tomorrow with as little risk as possible.
  • The securities are sold and simultaneously agreed to be bought back the next day at a slightly higher price — legally a sale, economically a secured loan.
  • The money is that price difference, which is the interest rate, plus the haircut protecting the cash lender against the collateral falling.
  • It goes wrong when the collateral falls faster than the haircut allowed, or when everybody wants cash on the same morning and nobody will lend against anything. Full page · haircuts

ETF

  • An investor wants a whole index cheaply and tradeably; a provider wants a fee on assets that require little decision-making.
  • The fund holds the index constituents (or a swap that replicates them), and authorised participants may create and redeem fund shares in large blocks against the underlying basket.
  • The investor's money comes from the index; the provider's comes from an annual fee, plus in some cases securities lending revenue.
  • It loses whenever the index does, and it under-delivers quietly through fees, tracking difference and tax on dividends — which is usually why a fund's return differs from the index it names. Full page · the gap, explained

FX forward

  • An importer knows they must pay in a foreign currency in three months and wants the price fixed today; a bank is prepared to fix it because it can hedge the position with two deposits.
  • Both sides are obliged to exchange the two currencies on the agreed date at the agreed rate, whatever the spot rate has become by then.
  • There is no premium: the forward rate simply builds in the interest-rate difference between the two currencies, which is arithmetic rather than a forecast.
  • The importer “loses” only in the sense of regret — if spot moves in their favour they are locked out of it, which is the price of having known the number three months early. Full page · hedging

Credit default swap

  • A lender wants to keep a bond but not the risk that its issuer defaults; a seller of protection believes that default is less likely than the market is charging for.
  • The buyer pays a regular premium for a fixed term; the seller is obliged to make the buyer whole if a defined credit event happens to the named issuer.
  • The seller's money is the premium stream; the buyer's is the payout, which arrives exactly when everything else they own is also having a bad week.
  • The seller loses suddenly and in size — this is an instrument whose losses are not gradual, which is why the position size matters more than the premium does. Full page

Autocallable note

  • An investor wants a high headline coupon in a market that is not paying one; a bank wants to buy volatility cheaply from a customer who is not thinking of it as a sale.
  • The note pays a coupon and redeems early if the underlying is above a level on an observation date; if it is below a lower barrier at maturity, the investor receives the fallen underlying instead of their money.
  • The coupon comes from the option the investor has sold without being told they sold one — it is the premium, repackaged as income.
  • It loses in exactly the scenario it was bought to avoid: a large fall, at maturity, with no early redemption to rescue it. Full page · why the protection did not protect

Money market fund

  • A company or a saver wants a bank account that pays a market rate; a fund manager wants scale on an instrument that requires very little judgement.
  • The fund holds very short-dated instruments — bills, repo, commercial paper — and offers daily dealing at, or very close to, a constant price.
  • The money is the yield on those instruments, less a fee, and the yield tracks the central bank's rate closely.
  • It goes wrong when everyone redeems at once and the underlying instruments cannot be sold fast enough at their marked prices — a run on something that was described as cash. Full page

Stablecoin

  • A crypto trader wants a dollar that settles at any hour; an issuer wants to hold the reserves and keep the interest they earn.
  • The issuer promises to swap a token for a dollar on demand, and holds — in the honest designs — short-dated government bills against every token in circulation.
  • The issuer's money is the yield on those reserves, since the token itself pays the holder nothing.
  • It breaks not usually because the reserves are bad but because redemption is temporarily unavailable, at which point the token trades wherever the secondary market says. Full page · is it stable

The drill

  • Pick a product you think you know. Set a timer for sixty seconds and say the four sentences out loud, without notes. Recording yourself is unpleasant and works.
  • Find the sentence you hurried. There always is one. For most people it is sentence three — where the money actually comes from — because that is the sentence marketing material never contains.
  • Then read only the part of the page that fixes it, and say the four again. This is faster than re-reading the whole page and it is the only part that changes anything.
  • Move outward by one step. Once ten products are fluent, do the same for a mechanism — leverage, liquidity, volatility — where sentence one becomes “who needs this and why” and sentence four becomes “when does it stop working”.
  • Then do it for a failure. Take any case study and tell it in three: what the position was, what moved, why the exit was not available. That is the shape of every one of them.

Two things that make an explanation worse

  • Starting with the payoff diagram. It is the last thing to say, not the first: a diagram describes the outcome and hides the obligation, and the obligation is the instrument.
  • Reaching for the exotic case. If the ordinary version is not yet fluent, the unusual one is decoration. Nobody has ever been marked down for explaining a plain instrument completely.