Perhaps being a brilliant decision maker means these days that you can make "big" decisions very quickly. I am very slow at making decisions, of any importance, because I would like to be in full command of the facts, or as many facts as are possible to command.
The speed at which we are encouraged to live, gives little time for full consideration of all the pros/cons. Perhaps someone who can make big decisions quickly is someone who does not feel the need to have all the facts at hand.
Furthermore, and this is only a suggestion, those same people who make quick, and therefore sometimes, wrong, decisions, do they feel less guilt when faced with the consequences of a bad decision. After all, can they justify their decision by saying "Well, no one else could decide, so I did".
In a nutshell, they make bad decisions because they are acting with haste. Some of us think more about our decisions and actions, and this process of reflection makes us unhappy.

Should I join in some threads in P & L now?

No, because by the time I have composed my response, any thread has moved on considerably.

I do often read P & L though.