I’ve gone out for lunch with Bob, Carol, Ted, and Alice and now it’s time to settle the bill. I only had a chicken salad and a soda but Bob had a steak and a beer, Carol had the pasta special and a glass of wine, and Ted a burger and coffee, while Alice just had toast and a glass of water. No surprise, now we can't agree on how much each person should pay ...
This isn't unusual because people generally aren’t very good at figuring our what’s a fair split so unless everyone is cool and agrees to simply divide the bill by the number of people it becomes a real pain. Think that's bad? Try dividing assets after a death or during a divorce; figuring out what’s fair often winds up usually becomes a knock 'em down and drag 'em out war of attrition.