The more you sell, the less the client trusts you to tell them the truth. The more you sell, the less inclined the client is to listen. The more you sell, the more you tend to look (and act) like a hammer looking for a nail – where any nail will do. In reality, the more you sell, the less you win. This position is entirely counter-intuitive to the average sales person, mostly because we are taught from the first day of sales training that the key to success is great sales techniques. You can find thousands of books.