Automatic site locale, timezone
Automatically create new sites with locale and timezone set to match the owner's
Eirik Yaempan Øra commented
We had a major issue with this problem. Admin set up the site a couple of years ago on US timezone (the default, it seems) while we work in Norway. We had bizarre time calculation issues and were just unhappy with the behaviour of the site. Even reported a bug.
Then figured out that the setting was wrong and corrected it. That led to a tsunami of issues as all the data on the site (all calendar entries e.g.) was shifted 8 hours to the side and had to be manually corrected.
Sharepoint can easily check on admin timezone vs site timezone and should put up a big red triangle saying that there is a mismatch!