What must actually happen for a destination to be validated? Asserting that the impact of local events is only a major component underestimates its fundamental causal mechanics.
It is not a simple adjustment, but a binary criterion that can suffice to invalidate a destination choice.
An event like the NATO Summit in Brussels can make a city unmanageable and hotel prices prohibitive for an average tourist.
The local event then becomes a sufficient exclusion condition, regardless of all other positive factors of the destination.