Deciding in advance what "wrong" looks like

An invalidation is the condition that proves your read was wrong. Not a feeling — a price, written down before you act.

Why this comes first

Without it, a losing position quietly becomes a long-term investment. There is always a reason to wait one more candle, and the reason always sounds good at the time.

With it, the decision is already made. Price hits the level, you leave, you go and find out why you were wrong later.

It is also where your stop goes

The invalidation and the stop are the same place. If they are different, one of them is a lie.

If the honest invalidation sits very far away, that is not a reason to move it closer — it is a reason to take a smaller size or skip the trade.

The usual mistake

Moving it once you are in. The moment you widen a stop because price is approaching it, everything you calculated beforehand is void.

This is for learning and is not investment advice.