SYSE.28:4.2 - Find where the property can change or be lost

Follow the relevant input, construction, transfer, installation and use. Identify which operations can alter the property and where another subject can be substituted. Do not assume that one label denotes unchanged bytes, configuration or material.

Locate the last relevant change before the prohibited reliance. Place a decisive observation or enforcing mechanism so that it can still prevent that reliance. Add earlier feedback only when it can avoid meaningful rework or guide a correction.

If the property can continue to change during use, determine what continuing observation or enforcement is needed and under what conditions it remains effective. A historical check cannot guarantee an indefinitely changing subject.