PESSIMISTS DRAIN your spirits and hope. I once worked with one who was enormously highly qualified, but had sunk into a severe depression, although well disguised. The first clue was how long it took to debrief simple encounters. The second clue were the 70 slide pitch decks. The third clue was that it was simply not fun being around him; it was exhausting and draining. Lesson: spot early and avoid pessimists!!