I think it must have been a leap of faith as there was no backups way back when.
There was that time when we had a car that wouldn’t go up a hill. The solution? Sans phone? I got out and pushed. Yes, it was successful.
There was also that memorable moment when the gear selector fell out of the engine. This was miles from civilization. We were on our own. I walked back five hundred yards and found the wretched thing. The dh then reinstalled it. We were good to go and did so.
Because there was no backup, we did the best we could to get with the program. Looking back, this is scary. It is also how it was.