We all experience perceived fails in our career. Failure is nothing to be embarrassed about so do not hesitate to describe a failure you've experienced in the past. The key to a great answer is to include how you learned from that failure, and how you improved your work performance after learning from the crash. Try to keep your example non-critical; for instance, avoid telling the interviewer how your team forgot to order new inventory, and it cost your company $15,000 in lost sales. Avoid blaming any particular person and instead, use words like 'we' and 'team' to describe the situation. Finally, be sure to tell the interviewer that, while you were very disappointed in the group's failure, you took the opportunity to learn from the experience.
"Our team was recently on a project with a very tight deadline. We knew the client and their needs very well which I believe made us go into the project overconfident. Because we underestimated the work involved, we missed our deadline by three business days. Thankfully we had a great relationship with that particular client, so we were able to recover from the missed deadline. Although it was late, we worked overtime and delivered an exceptional project, in the end. This experience taught me never to underestimate a project and the potential roadblocks. It's always better to under-promise and over-deliver, rather than the other way around."
"In University, we had a group project that failed horribly. We could not seem to organize our schedules at all, and so, when we brought all of the components together, it was a complete flop. I learned shortly after about some project management apps that could have helped. Also, we could have utilized other resources like Skype. This experience taught me never to think small, and that there is always a solution - you have to look for it."