Le mieux est l’ennemi du bien.
The best is the enemy of the good.

~ Voltaire (1694-11-21 1778-05-30 age:83) [François Marie d’Arouet Voltaire]

I have watched so many negotiations fail because both sides insisted on having it 100% their way. They both ended up with nothing at all since there was no agreement, no change. They each could have had perhaps 50% of what they wanted.