This old proverb used by skilled poker players, is no less applicable to partries negotiating a marital settlement agreement. Most parties have unreasonable expectations of what they must pay or receive if their case goes to trial. It is your lawyer's job to see to it that you have a fair appraisal of what the financial paramaters are if a judge decides the case, rather than you reaching a negotiated settlement.
For example, under present case law, the trend has been to award a spouse who has not contributed to a business venture, somewhere between 20 to 35% of the appraised value of the business. This is true even in marriages of long duration. However, as to non business assets such as a stock account or the marital residence, the tendency is to award 50% of the net value to each party.
When a support package must be worked out for both a spouse and children, there is ordinarily an award by the court that will not exceed 50% of the gross income of the paying spouse, and often somewhat less than such percentage. Awards vary between judges, so it is important for your attorney to know your judge's reputation for making such awards.
Armed with this knowledge, it will be a simple matter to know "when to fold then" and avoid the risk of a larger or lesser sum being awarded by the court, according to what side of the fence you are standing,