Orders that behave differently on exit than on entry

[Fairman]

Orders that behave differently on exit than on entry

A stop loss attached to a market order at entry can be accepted or rejected depending on the platform and moment. On some brokers, the stop must be added after the position opens, in a separate step. In between, the position has no protection.

For a scalper using speed, that gap is two or three hundred milliseconds. It sounds negligible. In a fast market, it's enough for price to move through the intended stop level before the protective order lands.

Platforms that accept stops with the initial order avoid this, but even then, the stop's validity depends on the price at the moment of execution. If the fill slips and the stop ends up too close to the market, the server may reject the order as invalid, leaving the position opened without it.

An expert advisor has to deal with that gracefully: check whether the stop was set after the fill and retry. A manual trader has to notice that the stop line is missing from the chart.

The simplest test is to place a market order with attached stop and target on a demo account during a volatile hour and check whether the stop was applied at the exact requested level.

Missing protective orders are an underrated cause of unexpectedly large losses.

Has a position ever opened without its stop, and how quickly was it noticed?