"Gaining is delusion, losing is enlightenment."
From Kosho Uchiyama, Roshi:
"To recognize true zazen, we have to look at our practice from an absolute perspective. If you are caught up in one of the limited kinds of Zen of the six realms, you can no longer see the essential point of buddhadharma. And what is that? As I said before, Buddhism teaches impermanence and the quality of non-ego. Letting go and opening the hand of thought is the foundation of Zen based on the buddhadharma.
The saying "gaining is delusion, losing is enlightenment" has very practical value. In our ordinary human life, we are always trying to fulfill our desires. We're satisfied only when all our desires are met. In Buddhism, though, it's just the opposite: it is important for us to leave our desire alone, without trying to fulfill them. If we push this one step further - gaining is delusion, losing is enlightenment - we're talking about active participation in loss.
Let me be clear that I am not saying, "Losing is important,
so go help people out by collecting what you can from them."
That just makes you the "someone" who gains. Rather,
apply this saying just to yourself and give something up. For
breaking the ego's grip, nothing is more effective than giving
something up." (Opening the Hand of Thought),
2004, P. 153)