Passengers told that there will be a half-hour delay are less unhappy than those left waiting even 20 minutes without an explanation. But even knowing how long we have to wait isn't the whole answer. We must also believe that everything is being done to minimize our delay. Larson cites the example of two neighbouring American banks. One was highly computerised and served a customer, on average, every 30 seconds. The other bank was less automated and took twice as long. But because the tellers at the second bank looked extremely busy, customers believed the service was faster and many transferred their accounts to the slower bank. Ultimately, the first bank had to introduce time-wasting ways of appearing more dynamic.