Vantaggi
If you are favourite employee of your manager then you no need to do any documentation. From his list of unfavoured, he will assign someone for you who will do documentation. If you are favourite employee of your manager then you no need to do work hard, He will give you promotion easily. Doesn't matter in your tenure you have done any assignment successfully or not. If you are favourite employee of your manager then you no need to do work hard, You will get onsite for too many years without knowing even compilation, Including this he will stop hiring for that location and will provoke other good resources to leave company because of saving your daily-allowance. Now question is how to come in good list: Do lunch with him, do fake praise of him, Late night parties with him, Booze with him and sutta with him.
Svantaggi
Nothing bad, all are good as I mentioned above.