My experience has me at the point where I won't go into detail explaining why I don't take s position. I tried when I turned down a government contractor for a position maintaining a couple servers for a position where I would be responsible for a few hundred for a lot less. They just pushed the money and got offended not understanding I needed the challenge and learning experiences. I left the situation feeling a little guilty and then just figured out you need to do what's right for you and not get into explaining it to people who won't even remember you in a few months.