I've been on both extremes - single carry-on (with no personal item, or a laptop in a bag solely to watch movies on the plane) for a two week vacation, and chec

I've been on both extremes - single carry-on (with no personal item, or a laptop in a bag solely to watch movies on the plane) for a two week vacation, and checked bag for a 3-day work trip. It depends entirely on context. Purpose of the trip, length of the trip, optionality with extending the trip, how locked in your itinerary is, all can play a role in whether it makes sense to pack a little, pack a lot, and whether you expect to use everything. I took a checked bag on my last < 1 week work trip and didn't use 2/3 of what I brought but I'd bring the exact same bag if I had to because you never know what might come up.