[latchkey]

I worked in a system a long time ago where someone came up with the bright idea of running batch jobs in such a way that the job would complete by the time we were in the users timezone morning hours. You know, so they could get the data when they were awake.

As time went on, the jobs started taking longer and longer and eventually took longer than the whole local morning, which resulted in them being awake AND being able to complain about it. The other issue was DST... users who were used to waking up and getting their data right away... would either be delayed an hour, or be done an hour early. Sometimes, the jobs would also run 2x or not run at all.

It was an utter mess of unintended consequences.