When it comes to measuring success for Instagram Stories, there are several key metrics that a product manager could focus on: 1. Engagement rate: This metric measures the percentage of people who engaged with the Stories content, such as by tapping through to the next Story or swiping up to visit a link. A high engagement rate indicates that the content is resonating with the target audience. 2. Completion rate: This metric measures the percentage of people who viewed the entire Story. A high completion rate suggests that the content is compelling and holds the viewer's attention. 3. Reach: This metric measures how many unique viewers saw the Story. A high reach indicates that the content is being distributed effectively and is reaching a wide audience. 4. Click-through rate: This metric measures the percentage of people who clicked on a link within the Story. A high click-through rate indicates that the call-to-action is effective and is driving traffic to the desired destination. 5. Conversion rate: This metric measures the percentage of people who completed a desired action, such as making a purchase or signing up for a newsletter, after clicking through from the Story. A high conversion rate indicates that the Stories content is not only engaging, but is also driving business results. It's important for the product manager to set specific goals for each of these metrics, and to track and analyze the data over time to identify trends and areas for improvement. Additionally, the product manager should work closely with the content creators to ensure that the Stories content is aligned with the overall marketing strategy and is tailored to the target audience.