This is an area where people can easily disagree. Could I pack light enough for a 1-2 week trip so that I don't need to check a bag? Sure. But you know what?

This is an area where people can easily disagree. Could I pack light enough for a 1-2 week trip so that I don't need to check a bag? Sure. But you know what? I don't want to be washing clothes in the hotel sink, or sending my laundry out, or go around wearing more and more deodorant to try and avoid smelling. My carry-on is a backpack with stuff I either plan on using on the plane, or my electronics which I'm not going to check. And I'm not going to stick my bag under the seat just so that someone else can try and force a huge bag into the bin.