In over forty years of sales, I have learned what is most effective in closing sales, much of that the hard way. I consistently observe Sales Professionals committing the sins today that keep them from maximizing their effectiveness and earnings. Today's quote-unquote" Sales Training" simply does not teach sales professionals "How to Sell." Even MBA programs at the best business schools, such as Wharton, Harvard, and Yale, never even broach the subject of selling. Selling has become a Lost Art.