Given that production units (decision making units) under
analysis in our study are road authorities, the observed efficiency
score can help us pinpoint some potential sources of inefficiency.
One important source of inefficiency is related to the maintenance
policies employed by road authorities, more specifically the
priority of PM, CM, and RM as well as the thresholds used for
deciding on the type of maintenance operation. Interviewing
maintenance managers and engineers revealed that in the current
practice, road sections in need of CM are given higher priority than
PM while allocating the limited budget. However, the policies that
were found through optimization pointed to alternative priorities
where PM is preferred over CM. Lastly, there might be alternative
decision-making structures that can provide improvement opportunities,
for example, the thresholds used to decide which road
segments are in need of maintenance operations as well as the
type of maintenance operations.