This is a copy of an earlier edit of my post, I just bring it forward, to make sure you guys will read it!
"For a sale to draw a consistent picture you have to know the product, maybe I don't know myself enough. Or rather something which is consistent for me, its not sure that it will be consistent to others who don't know me and they don't know why I say something. I never got use to be judged by my words, I always expected people to decide me based on what I do. Also a person with the minimum of sales skills has to know what it means to be consistent to people who they meet with at the first time. Unfortunately there are completely general ideas, if they are communicated in a "funny"/personal way or relation, even if they are true, can be appearing as completely "whack job" and inconsistent stuff. It doesn't mean you have to be the wittiest person to be able to communicate things about yourself unambiguously to strangers, you just maybe need a bit of practice. Sorry, but its not that easy for everyone for the first time. Especially not on a government level interview.
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