satisfaction function in present undesirable factors

data envelopment analysis (dea) is an efficient method to perform evaluation of units. in dea we try to evaluate units with undesirable factors in input & outputs by satisfaction function, testing some models. on the other hand benefiting this concept, we can identify non-efficient units. also we can recognize why these units are inefficient and calculate the reason of their inefficiency and how they turn efficient. in dea we cannot know why some units are non­-efficient and how these units can be efficient, but by this paper we can do this work.