In Québec, the default frequency for being paid is every two weeks. Big salaries are mostly stated as yearly salary, while more menial labour is often by the hour.
I don't have an explanation, it's just what it is. But I heard over that being paid every two weeks was because people were so bad with money that they would starve every month, so they started paying us every 2 weeks instead. Go figure.
That's a very good rule of thumb.