Sometimes packing for a trip is easy. You check the weather report, think about what you'll be doing and how long you'll be there, and pack accordingly.
Other times you might not be sure what the weather is or what you are doing the whole time, so it's a little more complicated.
And then you could be in my situation.
I'm flying home next Sunday. I bought a one-way ticket and I don't know how long I'll be gone exactly. It's also that fun time of year when the weather could range anywhere from hot to cold to rainy.
I have the added bonus of trying to move stuff home on the trip and not just packing for the visit.
Add to that the fact that airlines find it necessary to charge to check bags, and things start to get expensive and complicated.
Good thing I'm a professional packer. Otherwise, I'd be in real trouble.