Lots of wasted time. I am not a patient person. Wasting my time and the company/taxpayer's money really annoys me. People need to be a bit more aware of the other users. If they were going to run an overnight test and not going to show up till 9am, then they should have signed up for system time from 8pm till 9am.
Luckily, Lihn was helpful enough to allow me some of her time at 9am to try out my test. I've wasted a total of around 6 hours dealing with cleaning up the system when other people leave it in the wrong state.