A wick is a price the market reached and did not hold. In crypto the characteristic version is sharp, deep and fully retraced within minutes — and it usually has a mechanical cause rather than an informational one.
The mechanism
Price reaches a cluster of liquidation levels. The engine closes those positions with market orders, which consume the book. If depth is thin — a weekend, an off hour, a smaller coin — that forced flow travels a long way in seconds.
Then it stops, because the positions are gone. The selling was finite and mechanical, and with it exhausted, price returns to where the actual market is. The wick is the difference between the two.
What it actually marks
Where leverage was positioned, and how thin the book was at that moment. Both are facts about structure, and neither is a fact about value.
It is also a record of leverage removed. Those positions no longer exist, so that fuel has been consumed — the self-limiting property in why crypto volatility clusters.
The misreadings
As support or resistance. A wick low is a price at which forced sellers met an empty book. It is not a level anyone chose, and there is no reason for it to matter again.
As information. Nothing was learned about the asset. If anything the market demonstrated the opposite: at that price, real buyers appeared immediately.
As a trigger. Stops sitting inside wick range get taken out by a move that means nothing and reverses instantly. That is the most expensive way to be right about a market.
What follows one
Check whether the leverage actually cleared: open interest down, funding normalised from whatever extreme preceded it. If both, the crowded position has been flushed and the condition that produced the wick is gone. If neither, the positioning survived and the same wick can happen again.
And note that on a perpetual your own liquidation was judged on the mark, not the wick — which is why a wick through your level does not always take you out.