Tell me about a time you influenced a team without formal authority. What tactics did you use and what was the outcome?

What the interviewer is looking for:

The interviewer wants to know if you can influence and motivate others without relying on formal authority. They want to see that you can persuade team members, build consensus, and guide outcomes even as an individual contributor.

Example response:

When I was a software engineer at Acme Co, I wanted to improve our team's code testing practices. I knew adding more automated tests would reduce bugs and technical debt. However, I had no management authority to mandate or assign testing tasks at the time. To build support, I first recruited two other engineers who were excited about testing. Together, we built a prototype in our free time showing how automated UI tests could catch bugs early. We then demoed the prototype in our weekly team meeting and highlighted how it could improve product quality. This sparked a lively discussion and helped the team recognize the benefits of more automated testing.

I also worked one-onone with engineers, explaining how tests would make their features more robust and save them debugging time later. As momentum built, I volunteered to author our team's automated testing guidelines. Within two months of starting this effort, we had gotten buy-in from our whole 12-person team to adopt automated testing best practices and rotate testing duties. This drove a significant quality improvement for our product."