A few weeks ago, my wife, her sister and their mother set off from Orange County to Flagstaff. I asked my wife if she had a map, but she replied--we don't need a map, we've driven this before, etc.
So during the day they were driving, I called to see how the journey was going. First call reveals they got a late start, but are progressing north on I15 through the Cajon pass.
Later I call, and they are worse off. They should have been arriving at Flagstaff or nearly so. But instead of turning east on I40 at Barstow towards Flagstaff, they proceeded north on I15 from Barstow towards Lost Wages. They went far enough before realizing the problem, that they stopped back in Barstow for the night.
I got a really big laugh, for I'm the deatail oriented planner and calculator. The intuitive ladies may, just may learn but I doubt it.
I don't think maps or a GPS would have helped, since they were oblivious to outside evidence.