I have a little 22" carry-on suitcase and when I fly, it’s pretty much always international. I belong to this loosely-formed Rick Steves “One Bag Club”, and absolutely all I need for a 10-12 day trip fits into that thing, so no checked baggage fee for me. I also have a courier bag that goes under the front of my seat where I keep all the stuff I may need during the flight.
So I’m all legal, got my boarding pass, the correct seat and all I have to do is settle in, right?
Wrong. No room in my overhead compartment (again, not that I need it), but part of that space is mine, dammit. Somebody got on board with one of those over-size things and they caused everything to be shifted toward the front/back of the airplane. Oh yeah, what’s that announcement about “some of your bags may have shifted during the flight”? Bullshit. There’s no damn room for them to shift! 
I try not to be a Nazi about it, but it sure is a wrong way to begin a Trans-Atlantic flight.
Q