1.The last name stay with them for ever.
2.Phone conversation last 30minutes flat.
3.5 days vacation requires only 2jeans.
4.If somebody forget to invite them they can still be friends.
5.The same hairstyle last them for years even decades.
6.The can do shopping for 25 relatives in 25minutes.
7.They don't freak out when they go to a party and see another man wearing the same shirt instead they become buddies.

Let me know yours

#5 for sure, is one of the top reasons.