sbp/scalable — comment on commit 01d8d97a6d34b309699d4ad0e64f195219f34776
File: Makefile line 52
By sbp:

Another way to think about it is that a rule is a command saying that the target should be made when its dependancies are updated.

But an order-only dependency has nothing to do with updating, does it? That's why it's order only.