I mean, I'm not happy about this fact, but it's probably pretty typical.
1. pick it up at the store, then
2. unload it at home.
3. Had to rearrange because I put the wrong thing on the bottom.
4. Pick up each board to cut it,
4.5. some of them again to stain them
5. Again to assemble them into walls/roof/floor,
6. again to bring them from the garage to the site
6.5. Some of them again to put them on the floor
If I built sheds for a living I would most certainly optimize.