If you want to know how many cats are in my house, count them. If you want to know how busy the cat flap is, that's a completely different measurement, and it turns out almost nobody understands which one the market is reporting.

Because here's the thing about crypto prices that gets misunderstood more than any other single fact: the price is set by the last transaction, not by everyone who holds. It's a measurement of the flap, and people keep reading it as a census of the house.

Once that clicks, a surprising amount of market commentary stops making sense — in a useful way.

1. Price Is a Marginal Quantity

At any moment, an asset's price is simply what the most recent buyer and seller agreed on, for whatever quantity they traded.

If someone buys €500 of bitcoin and that trade happens at a higher price than the last one, the price is now higher. Not because bitcoin became more valuable to the millions of people holding it, and not because €500 changed anything about the supply. The price moved because the price is a record of the last agreement, and that was the last agreement.

Every holder's position gets revalued by that trade. None of them participated in it.

This is true of every market, but it matters enormously here, because crypto combines a huge nominal valuation with a comparatively small amount of trading at the margin.

2. Market Cap Is Not Money Invested

Now the big one, and the single most common error in this entire industry.

Market capitalisation = current price × total supply. That's the whole formula. It is an arithmetic product, not a measurement of anything that happened.

It does not mean that amount of money went in. It does not mean that amount could come out. If a token with 1 billion units trades once, at €1, between two people trading €100 worth, it has a "€1 billion market cap" created by a €100 transaction.

That's not an edge case. It is the mechanism, operating normally, at every scale.

Which means the phrase "X billion flowed into crypto this week" is almost always wrong by an order of magnitude or more. Research has repeatedly shown that a given amount of net inflow moves total market value by a multiple of itself — the multiplier varies with conditions and asset, and the direction of the error is consistent: the headline number is not money that arrived.

The same is true going down. A large decline doesn't mean that value was "withdrawn". Most of it was never deposited.

3. Depth Is the Missing Variable

What decides how far a given trade moves the price is depth — how much is resting in the order book near the current price.

A deep book absorbs large trades with little movement. A thin book gets walked up or down by orders that would be unremarkable elsewhere. This is why the same €10 million buy is a non-event on one asset and a 30% candle on another, and why weekends and small hours produce moves that look like news but are just absence.

It's also why "if this coin reached bitcoin's market cap" is a meaningless sentence. Reaching that valuation would require absorbing an enormous quantity of selling at every price along the way — the depth to do that is the actual question, and the comparison quietly assumes it away.

4. What This Changes in Practice

• Distrust "inflow" and "wiped out" headlines. Both describe changes in a multiplication, not movements of cash. They are the least informative numbers routinely published.
• Read supply, not just cap. Two assets at the same market cap with wildly different unit counts, unlock schedules and float are not comparable. Circulating supply excludes locked tokens that will arrive later — as sellers.
• Understand why your exit differs from your screen. A position's displayed value assumes you can sell at the current price. For anything illiquid, you cannot; selling is the thing that moves it. Paper value and realisable value are different numbers, and the gap widens exactly when you most want to close it.
• Respect thin conditions. Large orders in shallow books are how you donate money to the market via slippage.

5. The Part That Isn't Cynical

None of this means valuations are fake.

A price is real information: it's the current clearing point between everyone willing to buy and sell right now, and it aggregates an enormous amount of dispersed knowledge into one number. That's genuinely remarkable and it's why markets work at all.

It just isn't the thing people read it as. It's not a vault balance, not a measure of money deposited, and not a promise that everyone can exit at that level. It's a running report of what the last few people agreed on — precise, honest, and much smaller in meaning than the headline suggests.

The Point

The flap counts crossings, not cats. It's an excellent instrument for what it measures and useless for the thing people want to know, and most of the confusion in this market comes from reading one as the other.

Price is the flap. Learn to read it as what it is — the last agreement, at the margin, in whatever depth happened to be there — and most of the breathless coverage resolves into arithmetic.

Market cap is a multiplication, not a bank balance. 🐾⚡

Nothing here is financial advice — I feed a cat and write about Bitcoin, which qualifies me to advise you on neither. Do your own research.

Tags: Cryptocurrency, Bitcoin, Crypto Market, Market Cap, Investing