To look a gift horse in the mouth?

never look a gift horse in the mouth means don't overanalyze a favor or gift that has been given to you. This is only advice in the hopes that someone doesn't come across as a conceited d-bag. Like if you received a new GPS or something, this quote doesn't want you to look at it and say does it have satellite radio? does it have an mp3 player? can it identify a song? like you don't want to be greedy in receiving a gift is basically what it means.