It's on the list of the many things nobody teaches you in
   school: If you are not a confident extrovert, the world is not
   made for you. Need a job? You have to market yourself. Need to
   tell t...he teacher why you're late to class/don't have the
   homework? You need to sell the idea to the teacher. Sell sell
   sell. Those who are REALLY good at selling/marketing are often
   con artists or lack a conscience. (not all of course, but it
   seems to be common enough)."