During a planning session, the development team and the product owner disagree about the effort to deliver a feature: the product owner says one week, the team estimates two weeks. After hours of discussion they still haven't agreed. What should the project lead do?

The project team members are the ones who will perform the work, making them the most qualified to estimate the effort required. The project lead should facilitate understanding that the team's estimate is based on their direct knowledge and experience with the tasks involved. While collaboration is key, the team's technical expertise in estimating their own work is paramount for realistic planning. Unilaterally deciding the duration undermines team autonomy and commitment. Asking the team to accept a shorter estimate against their professional judgment leads to unrealistic expectations and potential burnout. Informing stakeholders of a delay without a clear resolution or re-estimation is premature and avoids addressing the core disagreement.