Traditionally, the project manager or ScrumMaster is responsible for evaluating a team's performance. But peer feedback, when each member of a team picks another member, observes him or her, and then shares thoughts and suggestions about that other team member’s work, can also be very valuable to continuous improvement.
One-on-ones aren’t for status reports. They aren’t just for knowing all the projects. They are for feedback and coaching, and meta-feedback and meta-coaching, and for fine-tuning the organization. If you are a manager and you aren’t using one-on-ones, you are not using the most important management tool you have.