Benefiting destinations may even be on a different continentThailand has suffered a succession of political crises causing a cycle of chronic downturns and upswings to its tourism industry. While Malaysia would seem to be the obvious alternate destination when a crisis occur in Thailand, the International Tourist Arrival data for Malaysia from UNWTO  does not seem to show any significant upturns when Thailand is negatively affected. Instead, Malaysia has had a slow but steady growth for the last ten years apparently unaffected by the tourism cycle of its northern neighbour.
Alternate destinations may even be on another continent altogether where a destination with similar touristic assets, like beaches and nightlife in Spain, may well be the unexpected beneficiary of Thailand's trouble.
In the Middle East, the combined losses of Egypt and Syria of more than 10 million tourists probably contributed heavily to the strong growth of tourism in UAE, although picking up mainly from the regional markets as altogether the Middle East countries lost nearly 7 million tourists to other regions of the world. Over the same period, South-East Asia gained 23 million tourists, far more than the global average and more than the Chinese tourism growth in the region, which would indicate that the region also benefited from the losses in the Middle East.
Recovering with a boom!There is a peculiar marketing aspect to tourism: a lost sale may not be lost forever, but simply postponed to another year. Most tourists have a list, however informal, of places they want to go in their lifetime. Thailand, the pyramids, New York, Machu Picchu, etc. When they have to select an alternate, the original choice is postponed to another year. Once a destination recovers from a crisis, the backlog is unleashed bringing a wave of tourists who had been awaiting for a better time to visit. Thailand is an excellent example of that where any year immediately following a crisis experiences a steep rate of growth followed by a more shallow increase in the year after that as the backlog has been absorbed. And as the market swings back to normal, the alternate destinations would experience a matching decline or slow-down in their growth bringing them back in line with their historical growth.
The point is that the global number of tourists is not reduced by local and regional crises, only by global economic conditions as can be seen in the UNWTO world statistics . Most of the 5 million tourists not going to Egypt are not staying home, they are going elsewhere. But when Egypt recovers, they will flow back to the loss of the destinations that initially benefited from the Egypt crisis.
 Tourism Highlights 2014, UNWTO