I have realized that I repack my bag several times as I am traveling, although to a limited degree. I have wondered if anyone else does something similar. I go through 4 phases.
In the first phase, I pack as tightly as possible to get to the airport with the least number of bags to contend with. The aim is to put everything in two bags with nothing left out so the chances of forgetting or losing something is lessened.
I'm the second phase, before going through security, I unpack anything that might cause the TSA to unpack my bags. For example, I pull out all the electronics and mechanical things, which travel through the x-ray in their own bag. I have had security completely unpack too many bags when something set off the need for further inspection. Chargers with lots of wires along with batteries and flashlights seen to have been the culprits, but you never know because they don't say. At this stage, two bags usually turns into four.
After clearing security, in phase three, I repack to get back to a carry on and a personal item, but things have to be shifted a bit. The idea is to move things to the personal item that I might want easy access to on the flight. Everything else goes into the carry on. The liquids bag gets separated into two categories, for example. Some things in the carry on get shifted to the personal item, such as a neck pillow or jacket. I have to move some things to the personal item, though, because the carry on is not that big and what I need in the personal item is fairly small. And, of course, I am only allowed to take two things in the cabin.
Phase four is basically restoring things back to phase one, and is done once I reach my destination airport. Things that spread out a bit on the plane need to be redistributed to reduce what I must manage carrying onward to the most concise set of bags.
I try to make the shifting around as manageable as possible by using packing cubes and bags, but it still feels like a production.
I might not have to go through all this if I used slightly larger bags and had more room, but I find that I keep returning to using the smallest bags possible to just barely hold what I am taking.