It's possible to get "lost" even with modern GPS.

My wife and I went on a backpacking trip in the wilderness some years ago. We decided to take a shortcut, bushwacking down a river drainage (1.5 miles) rather than taking the trail all the way around (7 miles) hoping to extend a later part of our trip.

We got downhill through the bushwhack to the bottom of the river valley just fine, but discovered at the bottom that a fire had come through the area a year or two prior. It had completely obliterated the trail, any markers, etc, and trees were fallen everywhere making moving in a straight line very difficult.

Despite having a phone with GPS and offline maps showing exactly where the trail "should" be, the lack of the trail actually existing combined with the challenging terrain made navigating out of the area a huge challenge. It was very easy to start wandering off in the wrong direction away from where the trail used to run without realizing and having to course correct back. I think we were moving at maybe 1/3 mile per hour, for 5-6 hours, until we finally made it out of the burn to where the trail existed again.