The missing side of tourism rebalancing: undertourism as a lower-bound diagnostic lens

This research letter reframes undertourism as the missing lower-bound condition within tourism imbalance. Rather than treating undertourism as low visitation, hidden-gem promotion, crisis-induced decline, or the opposite of overtourism, it argues that undertourism becomes analytically useful only when observed tourism activity falls below a locally justified benchmark at a specified spatial or temporal unit. The letter develops a bounded diagnostic logic that distinguishes undertourism from related causes, outcomes, perceptions, and policy responses, and explains why rebalancing should begin with diagnosis rather than promotion.