Service quality has been widely discussed in service management literature [1, 2]. Many
researchers have tried to define the construct. Generally, they have agreed that service quality
should be studied by using customer perspective [2, 22, 23]. Given this, researchers propose that
service quality is customer evaluation on the superiority of service performance provided by a
service company [28]. More clearly, Zeithaml [28] explained that service quality is “the consumer's
judgment about a [service]’s overall excellence or superiority”. Zeithaml [28]’s definition on
service quality is the widely quoted definition of service quality [28, 29].