Tell me about a time you failed. What would you have done differently?

This question is a typical example of a Behavioral question where the interviewer is trying to assess your attitude towards failure and disappointment. They want to understand how you have treated past failures, what you've learned from such experiences and how you have faced similar situations afterwards. They are not interested in your failures per se, but in your resilience, ability to learn, and your problem-solving skills.

In order to answer this question admirably, consider the following:

1. Select a real failure. Generic answers or unfounded hypothetical situations can harm more than help. They reveal a lack of self-awareness and the inability to learn from past experiences.
2. Focus on professional instances (unless otherwise specified). The interviewer aims to understand you in a professional context.
3. Explain what you learnt and how you improved. Your failure should be positioned as a growth opportunity that bettered you professionally.

While I was working as a project manager at XYZ Corp, my team was responsible for developing a mobile application within a set deadline. Optimistic about our efficiency, we decided to add on more features that were not initially planned in the scope. As the deadline approached, we realized we had overstretched ourselves and could not deliver the application on time with the extra features.

The project delay did not sit well with our client, and it was a significant failure that I regretted. But this experience taught me valuable lessons about the importance of managing scope. It also reinforced the significance of transparent communication with client stakeholders.

In future projects, I would only expand the project scope in consultation with stakeholders and with a clear understanding of the time implication. This failure was indeed a learning curve, and I grew as a professional manager as a result.

When I was working at ABC company, I was part of a team responsible for implementing a new customer relationship management system. We gave all of our attention to the technical aspect of the implementation and failed to realize the importance of employee training and acceptance. As a result, the system faced strong resistance from the employees and wasn't utilized as anticipated.

The failure on my part was not considering an essential aspect: change management. Looking back, I would pay equal attention to acceptance and training as to the technical part of any new system implementation. This experience was a profound lesson in the importance of taking a holistic view of projects and considering their human aspect alongside technical requirements.