Additionally, the impact of an explicit guarantee on purchase intent was strong for the good quality provider, but there was no change in the purchase intent for the outstanding provider. There are two plausible reasons for this. First, purchase intent was already high for the outstanding provider; hence it might have been difficult to boost the ratings much further. Second, the outstanding provider might have already captured the high-end of the market, even when it did not offer an explicit guarantee. Thus, the impact of providing an explicit guarantee would be minimal and it would be difficult for, for example, a highly rated hotel to attract new customers by signaling higher quality.Jochen Wirtz, Doreen Kum, and Khai Sheang Lee, "Should a Firm with a Reputation for Outstanding Service Quality Offer a Service Guarantee?" Journal of Services Marketing, 14, No. 6, 2000, 502–512
