The offensive line might be the only position in the entirety of team sports that is entirely passive. Their sole job is to protect or benefit others, by preventing defenders from tackling and hitting their players, whether it is in pass protection or in the run game. Of course, blocking itself—especially run-blocking—is not entirely passive, but the task itself is.
Because of the nature of the job, they tend to have a different mentality from what many other position groups might, with their sole focus being on simply doing their job. The variables don’t matter, because the one thing that never changes is their assignment: block.