Dropping 1m onto a hard floor is a lot worse than being slowly hoisted from horizontal to vertical.
If you disagree, I'll ride on the hoist and you can fall 1m headfirst onto concrete.
If you disagree, I'll ride on the hoist and you can fall 1m headfirst onto concrete.
That said, ugh's comment suggests my reasoning (as an explanation for vertical assembly) is either incorrect, incomplete, or both.