1. THOSE WHO LIVE IN MECHANICAL LIFE DUE TO SOCIAL PRESSURES, NEEDS & FEARS. THEY SHORTENED THEIR LIVE TIMES CANT FEEL LIFE OR LOOK THEMSELVES & AROUND 2. THOSE WITH NO MOTIVATION (WRONG BELIEVES / PRIORITIES ) 3. WITH PSYCHOLOGICAL IMPACTS OR SOME DISEASE OR UNHEALTHY LIVING ENVIROMENT

may be because people doesn't get satisfied , and always looks at at what others have.

If you know more you will be more tired ( positive relation)

The answer depends on what kind of people you are asking, Some people are real tired of the many things like a dead-end job, injustice. The others tired of being swindled by the politicians. There are people who don't see anything interesting around and spending the own live for self-compassion they can't stand and go ahead. I think that live is not a tired, but a week man can make himself to belief in tiredness of this world. In fact, that's not a difficult to add the colors to own live :)

they only saying it when they are tired of working or in a bad situation. cowboy...