Meaning of ‘Back out’ Phrasal Verb in English

She backed out of the deal at the last minute.

He agreed to help with the project but later decided to back out.

I can't believe he backed out of the job offer after accepting it.

They were supposed to attend the party together, but he backed out.

The company backed out of the partnership due to financial concerns.

She didn't want to back out of her promise, but circumstances forced her to do so.