An article that discusses burnout and compares it to overwork, which is less of an issue. Overwork is the result of working too many hours, a kind of physical exhaustion that can usually be diffused by simply going on holidays or sitting on a beach, whereas burnout happens at 
a deeper psychological level.

Burnout becomes a problem you are exhausted and you push on regardless, ignoring the problem and being in denial until something dramatic happens. Dramatic can be anything from hitting the wall emotionally to developing a stress-related disease – or worse.