In this example, the stated sequence of tasks is not open to question but we could
consider why there are two separate tasks, and ask whether they could be carried
out at the same time. If we investigated what could prevent the issue of the tickets
and cause a task other than ‘issue tickets’ to be invoked, we might find that:
The tickets could be available as an email download, and hence be issued
with the booking confirmation during ‘record ticket booking’.
The customer might not be eligible to attend – possibly on age grounds – and
so the booking would have to be rejected.