The mood of your trip depends on how it starts. If you're nestled between passengers who are dozing off on you, in front of an uncontrollable toddler, or beside someone who has bad body odor, you're probably not in the best mood for a vacation.
Last year I was on a 12-hour international flight beside an older man who couldn't stop coughing. There was a good hour that he had the hiccups, (which I know wasn't his fault.) It wasn't like I was going to sleep like a baby on the flight anyway, but I would have really enjoyed some quite time. I noticed that some people were starting to get frustrated by loud and irritating noise, which led to one woman to voice her dissent. Surprisingly, nothing was done.
I tried to confront him myself but he told me he didn't speak English and couldn't understand a word I was saying. I felt incredibly uncomfortable, and angry that none of the flight attendants could manage the situation. I'm really not sure what could have been done, but I told myself this probably happens on a lot of flights. Needless to say, my vacation started off quite lousy, and it really killed the mood of the rest of the trip.
A situation almost similar to mine happened on a flight from Dubai to Amsterdam on February 11, but there was a strange turn of events. A Transavia Airlines plane had to make an emergency landing after a passenger couldn't stop breaking wind. But that wasn't the only reason they had to land...