And people who are trying to lose weight or finish a project will sometimes make bets with their friends so that if they don't deliver on their promise it'll cost them money.

试图减肥或完成某项工程的人有时会和朋友打赌，这样，一旦他们不能兑现承诺，就会输钱。

youdao

Sometimes the best promise is to make no promise to those one that you care the most. Because you don't know when you gonna hurt them in a way that you can never make up to them.

因为当你给了对方一个美丽的童话世界而又亲手把这一切都摧毁的时候，你无法感受在对方的心中留下了的那一道永远无法填补的伤痕。

youdao

Why not make a promise on them?

BBC: Tattooists and tax

"We made them a promise that we would make this company a great investment for them, " he recalls.

FORBES: Magazine Article

Because everyone that tries to get into the Government spends all this time saying, "We're going to do this, improve that, make things better", and once they're in, not one of them does a goddamn thing to make it right, and to do what they promise that they're going to do.

BBC: News | NEWSNIGHT | Sharron Storer interview transcript