The full money picture has several moving parts, and trying to follow all of them at once gets confusing fast. Net liquidity boils it all down into a single line you can actually keep an eye on.
It starts with the big pool of money the Fed has created, then subtracts the two main places money gets parked and taken out of circulation — the government's own bank account, and an overnight facility where banks stash spare cash. What is left over is the money that is genuinely free to flow into the economy and into assets.
When that line is rising, there is more fuel available for prices to climb. When it is falling, the fuel is quietly being taken away — even if the news headlines have not caught on yet.