Did you ever notice that the more people that are on a meeting invitation, the more likely you are to mess up the time, date, duration, location, or conference call information for a meeting?

So if you are sending a meeting to your spouse, who loves you no matter how badly you mess up, the invite goes fine...even if it is a partially recurring, every other 3rd Wednesday of months with the letter R in their name, it's fine.

But if you have to send a meeting to a bunch of clients, their bosses, your PR guy, the CIO and some local politicians, it is guaranteed that your invitation process will look like this:

1. Draft the invite.  Proof several times.  Get a colleague to look it over.
2. Send the invite.
3. D' oh! you got the time right but for the wrong time zone.
4. Update meeting, with apologies
5. Double D' oh!  You got the time right but the date is wrong.
6. Repeat step 4
7. Breathe a sigh of relief. 
8. Receive e-mail that points out that the team in Canada will not be able to attend because it is the 2-4 holiday (What the heck is the 2-4 holiday????)
9. Pick a new date, repeat step 4, again.
10. Repeat step 7
11. Read new e-mail from the CIO that points out that while you got the date, time, time zone and topic right, you got the name of the client company wrong.
12. Repeat step 4, again....
13. Wait 30 minutes.
14. Repeat step 7.

Outlook Law #1 (OLL1): The probability of getting a meeting invitation correct on the first try is inversely proportional to the number of people on the invite list.

There's probably a corollary related to the stature of the invitees as well...

By the way, this effect really has nothing to do with Outlook as it applies to any scheduling system.  It just sounds good as OLL1.