It never pays. Economies grow, and growth makes for great investment opportunities. If you can't readily identify two or three simple reasons why a share is likely to move, stay away. It's often a good time to sell when elaborate research reports on a company start appearing. Beware of popular stocks.
Widespread enthusiasm can bloat values, mask weaknesses and make management complacent.
Look for substantial and sustained personal shareholdings by top management. Rich executives really do like to get richer.