Background: the service quality models
The context of service quality has not been perceived uniformly. Cullen (2001) for instance portrayed two sets of quality context: objective, and perceived quality; the first focuses on the standards and guidelines being set up by professional bodies, while the second pertains to customers' perceptions. Similarly, Gronroos (1984) abstracted the service quality into technical and functional. By and large, literature on service quality has been lined up behind the latest category while maintained a level of disintegration with the first. On the other hand, scholars have endeavored to improve service quality. Their models that conceptualize service quality improvement included the disconfirmation, perceived quality, SERVQUAL, and Six Sigma (Kasper, Helsdingen, and Gabbott, 2006:183). Additionally, Ahmed and Rafiq (2002:13) spelled out two other models namely Berry's model and Grönrros' model, but placed them within the context of the internal marketing theory. However, the preceding models perceived service quality from a narrow perspective; none have had a holistic view of quality. This explains the inconsistency in conceptualizing service quality where the perceived service quality endured to measure customers' satisfaction in particular.
Also, scholars have postulated different service quality dimensions. For instance, Hedvall and Paltschik (1989) went to identify two measured dimensions namely ‛willingness and ability to serve’, and ‛ physical and psychological access’; Lehtinen and Lehtinen (1982) articulated three dimensions: interactive, physical, and corporate quality embraced; Gagliano and Hathcote (1994) — citied in Fogarty and Gatts and Forlin (2000) — embraced four structural factors of quality corresponding to Personal Attention, Reliability, Tangibles and Convenience. Additionally, Sureshchandar and Rajendran and Kamalanabhan (2001) postulated the service quality dimensions to include service product features, systemization/ standardization of service delivery, social responsibility, service tangibility, and the human element of service delivery. Furthermore, the paradox of service quality constituents was framed into seven service attributes namely security, consistency, attitude, completeness, conditions, availability, and training ( Sasser, Olsen, and Wyckoff,1978— cited in Rowley ,1998). Finally, other quality dimensions of Haywood- farmer (1988:21), Becker and Wellins (1990), Gummesson (1992), Philip and Hazlett (1997:273-274), and Brady and Cronin (2001:44)— cited in Stiglingh( 2008)— have been portrayed as well.
Nevertheless, Rowley (1998: 329) suggested establishing a standard measurement scale (generic dimensions) that prevails to each single industry. By that he stipulated the issue of flexibility into its concrete perspective.
Questioning the flexibility of SERVQUAL gap measurement
Though SERVQUAL scale was embraced as a generic instrument for measuring