What do you mean ? Do you mean you shouldn't wait until you are too cold and weak to go out and seek help, or should not leave the vehicle at all ?
Waiting is the hardest work I know, but as an old country man of my acquaintance once said, "Don't just do something. Stand there."
Yah, that was not exactly clear. Rule #1 Don't leave the vehicle.Human nature is to stick around until they are cold, starving, or dehydrated. Once weakened, we will get a case of the homesies. The temptation has to be resisted.
I think it's a judgement call. Most of the time it will be better to stay put, especially if you know people will be looking for you, and they have a general idea of where you might be. But there was a case a few years ago, also in Oregon, of a man who died waiting to be rescued when unbeknownst to him, he was only a short distance from a well traveled road.
As others have said, the ideal thing is not to get into a jam in the first place, and be well prepared if you do.