Obviously, it is important to approach with some drive whatever job you happen to have. The funny thing about sales, though, is that approaching a prospect with a high outward degree of feeling may bring an outcome exactly the opposite of what you would like, i.e., a deal.
While it is foolish to deny to yourself that you want or need the deal, it is equally wise to deny the prospect the opportunity to infer this. By giving her that pleasure, you may rob yourself the pleasure of a signed contract, and the compensation that comes with it.
Approach each prospective deal with the proper amount of eagerness.