The main reason is because they get frustrated and not having fun.
The good news is that very often this situation does not depend on the student’s approach, but is simply generated by a wrong choice of guitar and, even more, by the often not well designed learning method.
There are many self-described guitar teachers who think they can teach others simply because they can strum a few chords.
Always look for an experienced and established guitarist if you really want to learn to play.
