Perhaps of all the suggested special characteristics of service products, this is one of the most difficult to appreciate. Why? Services are highly perishable compared to physical products. But how could, for example, the services of say, an airline be considered to be more perishable than, say, fresh food and vegetable products?
The reason is that unlike most physical products, many services cannot be stored. For instance, if an airline does not sell all the seats on a particular flight, then those seats or rather the sales revenue of filling of them would have carried, has immediately and irreversibly gone.