I remember my first exposure to this as a child in the early 80s, a friend of my parents was long term unemployed and I couldn't understand it. My mother's (somewhat unsympathetic tbh) explanation was that he wanted his old job back and that it no longer existed. He did eventually find gainful employment, but in another field.

A little off topic, but a functioning welfare system has the potential to allow people to take the time to find the right job, rather than be pressured into taking the first thing that comes along. It's a question of balance