Negotiation properly done is each side gradually, as it gains trust in the other, exposing what it feels it needs to get from the negotiation. As I emphasize often, this does not mean stating a "position" but listing needs. Often a position focuses on price, only one part of real world deals. And it contemplates a back and forth auction. I advocate instead persuading the other side and yours that the appropriate price is one based on fair and objective standards. A "position" has no place in this process.
If the final price is fair and objective, then neither side has left money on the table and both have as closely as possible had their needs met.