To fail at the last moment, just when success seemed certain; to fall at the final hurdle.
经过团队成员数月的努力，这个项目本来已经接近尾声，却因为一个突发的技术难题而事败垂成。
After months of effort from the team members, the project was nearing completion, but it failed at the last moment due to an unexpected technical issue.
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