For example, the cost of degrading a given site will be less if there are several alternative sites that can be used instead (all else equal). For example, the value of a site can be affected when quality is improved or degraded: not only does value associated with the experience increase/decrease but this may also affect the number of people who visit the area, which affects overall value. Further, some users (e.g., mountain bikers and skiers) have become more accustomed overtime in some areas to paying an entrance fee, compared to other types of uses. This suggests the importance of collecting appropriate data on user preferences and attitudes.