Stop Loss (Mechanical)

A stop loss is usually taught as protection, which is correct from the trader's perspective. Mechanically, however, it is a conditional market order waiting for a trigger. When price reaches that trigger, the stop becomes a demand for immediate execution.

If you are long, the stop becomes aggressive selling. If you are short, it becomes aggressive buying. It then consumes whatever opposing liquidity is available, just like any other market order. The trigger price tells the order when to activate; it does not guarantee the exact price at which the entire order will fill.

This is why stop placement has market consequences beyond a line on your chart. Stops clustered around obvious highs and lows can release waves of aggression when triggered. Whether that wave is absorbed or drives further relocation depends on the liquidity waiting on the other side.