The “P-F Interval” concept is a deceivingly simple idea or
concept. It assumes that we have been able to defined “P” –
the potential-for-failure point. The potential-for-failure point can
be problematic to define or determine. Additionally, the curve
implies that we can identify a single condition indicator that
dependably tracks the resistance-to-failure of an object to a
single condition indicator and that the point at which the
resistance to failure starts to breakdown and the failure point for
the object can be defined. If we can do this then it is implied
that we have identified a period of time within which to rectify
the situation before failure of the object under study will occur