I'll gladly repay you the second Tuesday of next week.

My newest issue of Brainmail appeared in my inbox this week, and as usual, it is full of interesting tidbits, most that make me say, “huh?”  Here is one that struck me like a ton of bricks, not because it was odd, but that it made so much sense:

 Here is interesting story about human behaviour. A   childcare centre in Israel was having problems with parents that were picking their children up late. As a result they introduced a fine for lateness. The result was that lateness increased. Why? Because the fine normalised the behaviour.

Makes me wonder: if you include a late fee provision on your bill, does it make your client more likely to pay late?