A list built for your actual trip — with quantities that combine, and the things that genuinely can't go in the hold.
Nothing goes with anything. Five tops that work with two bottoms is ten outfits; seven of each that clash is a heavy bag and the same three combinations.
The fourth pair goes unworn on almost every trip, and takes the space that made the bag too big to carry on.
Charger, adapter, medication, the thing you bought specially. All cheap at home and expensive at an airport.
Power banks, spare lithium batteries, prescription medication. Put them in the wrong bag and it's not an inconvenience — it's a problem at the gate.