Here's an information graphic from a Wall Street Journal article about the problem of wait-time:
The article itself is a bit of a mess, choppy and superficial, but it speaks to a rather serious problem with home delivery and on-site services. Firms offer customers a broad window (sometime between 9 am and 3 pm on Tuesday) and then fail to keep that appointment.
There are snippets of information about it being more than a minor inconvenience - a survey is mentioned that more than half of adults use vacation time and more than a quarter have lost wages in order to wait. The implication is that the financial cost of waiting can be measured.
However, the quantifiable factors are far less damaging than the qualitative ones. Consider the responsess in the information graphic above: companies "don't care about" or "take advantage of" their customers or thye lack the competence to predict the activities of their own people or suppliers.
In all, this is a factor that merits far more consideration that it is evidently getting.