Tell me about a time you failed to meet a commitment

We all face challenges and setbacks in our careers. I'm interested in understanding how you navigate those situations, especially when commitments are involved. Tell me about a specific time when you committed to something, either at work or in a significant project, but were ultimately unable to fulfill that commitment. What were the circumstances, what actions did you take to mitigate the situation, and, in retrospect, what would you do differently now?

Answering the Interview Question: Tell me about a time you failed to meet a commitment.

As a Senior Software Engineer at Google in Mountain View, I've learned that sometimes, despite your best intentions and planning, things don't always go as expected. One situation that comes to mind involves a critical feature release for Google Photos.

Situation

We were tasked with implementing a new collaborative album feature, allowing users to easily share photos with friends and family and have them contribute. The initial estimate was aggressive, but the team felt confident we could deliver within the given timeline. I was responsible for the backend service that handled the album metadata and sharing permissions.

Task

My specific commitment was to ensure the service could handle the projected load of new collaborative albums and provide robust access control, preventing unauthorized access to shared photos. This involved designing and implementing new database schemas, API endpoints, and authorization logic.

Action

Initially, progress was good. We were hitting our milestones and code reviews were going smoothly. However, as we approached the final weeks of development, a few unexpected complexities arose. Firstly, we discovered a performance bottleneck in our database queries when handling albums with a very large number of contributors. Optimizing this took significantly longer than anticipated, requiring a redesign of the query strategy and extensive testing.

Secondly, a critical security vulnerability was identified in our initial authorization implementation. Fixing this required a complete rewrite of the authorization logic, adding additional layers of security checks to prevent potential exploits. This vulnerability was caught late in the game by our internal security audit team.

Because of these two unexpected hurdles, I failed to meet the original deadline for the backend service. I communicated this to the project manager and the team as soon as I realized the severity of the delays and the impact on the overall release schedule. I provided a revised timeline with a detailed explanation of the challenges we were facing, and outlined the steps we were taking to mitigate the impact. We worked extended hours, prioritized the most critical aspects, and coordinated closely with other teams to minimize dependencies.

Result

While we ultimately launched the collaborative album feature, it was released a week later than initially planned. Although the delay was relatively short, it still impacted other teams relying on my service, and it was a stressful period for everyone involved. More importantly, it taught me valuable lessons about the importance of thorough risk assessment, contingency planning, and proactive communication.

Lessons Learned

Since then, I've implemented several changes to my work process. I now dedicate more time to risk assessment and contingency planning early in the development cycle. I also strive to communicate potential issues and delays as soon as they arise, providing realistic timelines and transparent explanations to stakeholders. Furthermore, I've made a concerted effort to improve my understanding of our systems' performance characteristics and potential security vulnerabilities, enabling me to better anticipate and address challenges before they escalate into significant delays.

I also now advocate for more frequent security audits, not just at the end of the development cycle but throughout the entire process. This helps catch vulnerabilities earlier, when they are easier and less costly to fix.