To think what one should not

A novice coming into a really big demanding position.
Enthralling as it may sound, its a case of misplaced thoughts.
Atleast this is what happened to me once.

Following is a slightly "metaphoric" situation for the one that happened:
I was in army.
Was called up to serve in the WAR.
Performed really well.
Gunned down many enemy men.
Saved a few of my own mens lives.
Came out of age on certain instances, turning the tide for my country.
Then we lost a few men. A few injured, a few released from the pain.
The leaders were scarce and some new leadership was badly needed.
I was given the opportunity.
This meant to carry out some high profile surveillance mission.
Now what should I think at this moment...
Why was I thinking about the success I have achieved.
Why was I thinking about the great things I will do.
Why wasnt there a caution alarm ringing aloud in my brain...

Today I saw a colleague being in the same state.
Seems that I have realised where it all went wrong or rather I actually learnt a few lessons from that.