Every watch that leaves the bench gets wound by hand for its two-week regulation period, even the automatics. It’s slower, and it means someone has to remember to do it every morning.
But winding a movement by hand is also when you feel a problem — a rough spot in the mainspring, a crown that doesn’t quite seat right — days before it would show up on a timing machine printout. We’ve caught three faulty barrels this year that way, all before a single watch shipped.
It’s not a scientific argument for hand-winding. It’s just that a hand catches things a graph doesn’t, and we’d rather find the fault ourselves than have a customer find it in six months.