Quality

Duality applies to Quality as well. Good can't exist without evil, Light has no significance without darkness - Higher(good) quality has no meaning without the lower(bad) one.

Extreme of any good quality turns it into a bad one. Like...

• Cynicism helps but then it invariably leads to paranoia. 
• Confidence turns into cockiness. 
• Desire to succeed turns into an unwillingness towards acceptance of failure.
• Strong leader turns into a dictator.
  

Lack of quality won't solve any problems either. So it's as good as a bad quality when one is incapable of doing what he should. Like...

• Lack of light leads to darkness.
• Lack of cynicism makes one gullible.
• Inability to act makes one the obstacle.

People say pick up positives not negatives but what makes you say that they're exclusive? What makes you think that they're distinct? If good and bad were so different then how could a gray area ever exist?

With great powers come great responsibilities

I know this is cliched and seems irrelevant to us, I mean most of us aren't saving the world in any obvious kind of way. But I still feel that this phrase is quite pertinent to our lives. Our qualities determine our strength as well as weaknesses. They bring us great powers which need to be handled responsibly. We need to maintain balance because either extreme results in something that the quality was there to prevent in the first place. This might explain why happiness, triumph, success and every other thing associated with a good balance are so short lived.