I have found that the most frustrating thing is when the "escalation" for non-attendance/bad behaviour in a detention does not work. Failure to attend your detention -> put in departmental detention. Failure to attend that -> put in the weekly "school" detention. You go to do that (already a week down the line from the incident), and you find that they're already in for the next two weeks, one of those being because they failed to turn up last week. Meanwhile, the same child is continuing to accrue "class teacher" detentions at the rate of several a week, knowing that it will never catch up with them.