Sensitivity point

A sensitivity point is an element of an architecture or system that influences more than one quality attribute at once. If a single component is responsible for both a system’s runtime performance and its robustness, for instance, that component is a sensitivity point for both attributes. A change to the component moves both qualities, whether or not that was the intent.

Put crudely, mess up a sensitivity point, and you will usually have more than one problem.

Sensitivity points matter because they concentrate risk. Change one, and the effects ripple across every quality attribute it influences, which is why they are treated as the places in a design most worth scrutinizing during a qualitative architecture evaluation such as the Architecture Tradeoff Analysis Method (ATAM).

A sensitivity point where the affected attributes pull in opposite directions – improving one degrades another – is more specifically a trade-off point.