A well-defined IFR helps a problem solver to overcome psychological inertia and reach breakthrough solutions by thinking about the solution in terms of functions, not the intervening problems or needed resources. It focuses on functions needed, not the current process or equipment.
The idea of formulating the IFR is to clearly define the goal of improvement and eliminate rework (solve the right problem initially).
A basic concept of TRIZ is that systems evolve towards increased ideality (functionality), where the extreme result of this evolution is the Ideal Final Result:
The ideal system
is acting as pure function, because it:
The Ideal Final Result also is a step in ARIZ.