The bag packed in haste reveals what your attention reached for first.

With time, packing is a matter of lists and sensible judgement. Without it, your hands make the decisions, and what they pick tells you what you have genuinely been holding onto. The results are frequently surprising: the practical item forgotten, the meaningless one taken, the thing you would have argued you did not care about sitting on top.

If you have ever packed in a rush, think back to what came with you. Considered as evidence rather than as a mistake, it is a fairly honest account of what you rely on.