According to Table 4, it can be observed that the groups assigned different scores to the same
failure. After analyzing and discussing this fact, we concluded that the difference in the
scores can be attributed to two main reasons: First, one restaurant was far better than the
other, and second, the participants of each group had different interpretations regarding the
level of the customer perception. This point was exhaustively discussed since, when FMEA is
used in products, the failure mode and effect are well defined. On the other hand, in the case
of services, there is also the subjectivity in the form the attendants perceive what they are
doing and how the customers are reacting.
Therefore, we used the mean and the range of the scores for each group, in order to detect a
significant discrepancy among the groups. Table 5 shows the final result. It can be observed
in the most subjective items, such as badly-set table or impolite employee, that there was a
higher discrepancy in the scores for the different groups. The items “delay” and “cleaning”
shows a more homogenous result.