Let's begin with the boys, ahem, and gents. Suits-check, Shoes-check, cravats-check, cummerbands-check, hair and grooming-check. Or is it? Some of your friends who commit may take forever to fit their wardrobe and you have to keep sending out reminders via email, text and calls like you're paid to do it. Same goes for the ladies. She loses weight in the first 6months, then it catches up with her in the last two months and the fittings become a nightmare changing sizes and whatnot. Ok, maybe that is a worst case scenario but I think over the short time I have been involved in wedding preparations, the tailors are the most annoying.
You've paid for the dresses, material and design and the bungling seamstress fails to meet deadlines upto a week to the wedding. Never mind that you were there on time almost 6+ months prior to D-Day!
Then the harrowing task of trying to synch everyone's schedules for meetings so the maids and groomsmen can get to know each other at least face-wise before the wedding day. Meetups for fittings and shoe buying, making sure everyone in the party is comfortable with what you are asking them to wear and ensuring they all make it to the venue and aren't in a different time-zone altogether because of either work or family issues.
This forms the basis of our first discussion. Now to hunt for the couple that will be the first to share their line-up woes or joys =)