KPIs for Product Managers

KPIs for Product Managers: product stability

Discover the top KPIs for Product Managers to measure product stability and ensure a seamless user experience.

Product stability is a crucial factor for any product’s success, whether it's a software application, a mobile app, or a physical product. It refers to the product's ability to perform consistently over time without crashing or encountering significant issues. Establishing and maintaining product stability is a vital responsibility of product managers, who track various performance metrics and KPIs to determine how well their products are performing. In this article, we will discuss the importance of product stability, the key performance indicators (KPIs) that product managers should track, and how to monitor and improve product stability over time.

Understanding the Importance of Product Stability

Product stability is a critical aspect of any successful product. It refers to the ability of a product to function consistently and reliably under various conditions. In today's fast-paced digital world, where customers have high expectations for seamless experiences, product stability can make or break a product's success.

Product stability is essential for ensuring customer satisfaction and retention. When a product is stable, it functions as intended, and users can complete tasks without encountering errors or bugs. This positive experience can lead to increased customer loyalty and advocacy, which, in turn, can boost a product's reputation and revenue.

On the other hand, when a product is unstable, it can negatively impact user experience, cause frustration, and lead to bad reviews or even the loss of customers. Furthermore, instability can increase the workload for customer support teams and lead to longer resolution times for fixing bugs and errors.

By prioritizing product stability, product managers can avoid these outcomes and ensure that their products are reliable and user-friendly. This, in turn, leads to increased customer satisfaction and retention, higher revenue, and reduced long-term costs associated with fixing errors and addressing customer complaints.

Defining Product Stability

Product stability is not necessarily a black-and-white concept, as different products and industries may have varying stability requirements. However, there are common factors that contribute to stability, such as uptime, response time, error rates, and crash rates. Thus, monitoring these KPIs is crucial to determining a product's overall stability.

Uptime refers to the amount of time a product is available and functioning correctly. For many products, especially those that provide critical services, uptime is a crucial factor in determining overall stability. For example, if an e-commerce website experiences downtime during a busy shopping season, it can lead to lost sales and frustrated customers.

Response time refers to the amount of time it takes for a product to respond to user requests. A slow response time can negatively impact user experience and lead to frustration. For example, if a mobile app takes too long to load, users may abandon it and switch to a competitor's app.

Error rates and crash rates refer to the number of errors and crashes that occur within a product. High error and crash rates can indicate instability and negatively impact user experience. For example, if a software program crashes frequently, users may lose their work and become frustrated.

Why Product Stability Matters for Product Managers

Product managers are responsible for ensuring that their products meet specific quality standards and performance metrics, including stability. When products are unstable, it not only increases the risk of losing customers but also negatively impacts a product manager's reputation.

Monitoring and improving stability is, therefore, essential for ensuring that a product manager is perceived as competent and effective. By prioritizing stability, product managers can ensure that their products meet customer expectations and provide a positive user experience. This, in turn, can lead to increased customer loyalty, revenue, and overall success.

Key Performance Indicators for Product Stability

Ensuring product stability is crucial for any product manager. A stable product ensures that users have a positive experience and are more likely to continue using the product. There are several key performance indicators that product managers should monitor to determine a product's stability. These include:

Crash Rate

The crash rate is the ratio of the number of crashes to the number of users over a specific time period. A high crash rate indicates that the product is unreliable and prone to errors, and negatively impacts user experience. Product managers must monitor the crash rate to identify the cause of crashes and take action to mitigate them.

For instance, if the crash rate is high, the product manager can investigate the root cause of the crashes. They can analyze user logs and error reports to determine the specific conditions that lead to the crashes. Once the cause is identified, the product manager can work with the development team to implement fixes and test the product thoroughly to prevent future crashes.

Mean Time Between Failures (MTBF)

MTBF is the average amount of time it takes for a product to fail or encounter a critical error. This KPI allows product managers to determine how frequently critical errors occur and use this information to prioritize improvements that will increase stability.

For example, if the MTBF is low, it indicates that the product is prone to critical errors, which can negatively impact user experience. The product manager can work with the development team to identify the most common critical errors and prioritize fixing them. Once the errors are fixed, the product manager can track the MTBF to ensure that the product is becoming more stable over time.

Error Rates

Error rates indicate the frequency with which user requests or actions result in errors or failed attempts. High error rates indicate that users are not having a positive experience with the product, and can lead to frustration or abandonment. Tracking error rates allows product managers to identify patterns and prioritize improvements to reduce errors over time.

For instance, if the error rate is high, the product manager can analyze user logs and error reports to determine the specific types of errors that users are encountering. They can work with the development team to prioritize fixing the most common errors. Once the errors are fixed, the product manager can track the error rate to ensure that the product is becoming more stable over time.

Latency and Response Time

Latency and response time measure how quickly a product responds to user requests or actions. Quick response times and low latency are crucial for ensuring a positive user experience, and high latency or slow response times can be frustrating and lead to abandonment. Product managers monitor these KPIs to ensure smooth and responsive user experiences.

For example, if the latency is high, the product manager can work with the development team to optimize the product's performance. They can identify the specific areas of the product that are causing slow response times and work to improve them. Once the improvements are made, the product manager can track the latency and response time to ensure that the product is becoming more responsive over time.

System Uptime

System uptime measures the amount of time that a product is fully operational without experiencing critical errors or crashes. High system uptime is indicative of product stability, while low system uptime indicates instability. Product managers track uptime to ensure prolonged product stability and identify areas requiring improvements.

For instance, if the system uptime is low, the product manager can work with the development team to identify the specific areas of the product that are causing instability. They can prioritize fixing the most critical issues to increase system uptime. Once the issues are fixed, the product manager can track the system uptime to ensure that the product is becoming more stable over time.

By monitoring these key performance indicators, product managers can ensure that their products are stable and reliable, providing a positive user experience and increasing user satisfaction.

Monitoring and Improving Product Stability

To ensure product stability, product managers must monitor KPIs regularly and take actions to improve them. Here are some steps that product managers can take:

Setting Stability Goals

Product managers must set stability goals that align with the company’s objectives and customers’ expectations. These goals should be specific, measurable, achievable, relevant, and time-bound. Sit with your development team and understand the architectural requirements of your product. This will help you set realistic stability goals that can be achieved through effective monitoring and improvements.

For example, if your company’s objective is to increase customer satisfaction, your stability goals may include reducing the number of crashes or errors experienced by customers while using your product. This will require you to monitor stability KPIs such as crash rates, error rates, and uptime.

Identifying Root Causes of Instability

Identifying the root causes of instability is critical to improving stability over time. Conduct a thorough audit of the product’s codebase, identify components causing instability, and update system dependencies. Bug fixing should be a priority over new feature development.

During the audit, pay close attention to the areas of the codebase that are causing the most instability. This will help you prioritize your bug fixing efforts and ensure that you are addressing the most critical issues first. Additionally, make sure that your development team is aware of the importance of stability and is actively working to address any issues that are identified.

Implementing Stability Improvements

Once the instability causes have been identified, product managers should implement improvements to address them. These improvements can include code optimization, dependency updates, and load testing to prevent future instability instances.

Code optimization involves reviewing the codebase and making changes that improve its performance and stability. This can include removing unnecessary code, improving code structure, and optimizing algorithms. Dependency updates involve updating the libraries and frameworks used by the product to their latest versions. This can help to address any security or stability issues that may be present in older versions.

Load testing involves simulating high levels of user traffic to identify any performance or stability issues that may occur under heavy load. This can help to identify any bottlenecks or scalability issues that may need to be addressed.

Tracking Progress Over Time

Product managers should track stability KPIs regularly to determine whether the stability goals set are being achieved. Monitoring KPIs allows managers to detect any deviations from the stability goals and to take corrective action quickly.

Make sure to communicate the progress being made to the rest of the team and the company as a whole. This will help to build confidence in the product and show that the team is actively working to improve its stability. Additionally, celebrate any milestones or achievements that are made along the way.

By following these steps, product managers can ensure that their products are stable, reliable, and meet the needs of their customers. This can help to build customer loyalty and drive business growth over time.

Balancing Stability with Other KPIs

While stability is vital, product managers must maintain a balance between stability and other performance metrics, such as new feature development and product performance. Here are some considerations that product managers should keep in mind:

Prioritizing Stability vs. New Features

Product managers should strive to achieve stability goals while still releasing new features. However, they must weigh the risks and benefits of each new feature release. Testing procedures, pre-release evaluation, and mass usage of the product should help with measurement.

Managing Trade-offs Between Stability and Performance

Product managers should evaluate the trade-offs between stability and performance budgets. An overly strict stability budget can restrict innovative opportunities while a large performance budget can severely compromise stability.

Ensuring User Satisfaction and Retention

Ultimately, user satisfaction should always be the highest priority. Increasing user retention, reducing customer complaints, and improving user satisfaction ratings will help steer product managers towards the right balance between stability and other KPIs.


Achieving product stability requires product managers to regularly monitor stability KPIs, identify the root causes of instability, and implement improvements. While balancing stability with other KPIs can present a challenge, a focus on stability can lead to increased customer satisfaction, retention, and revenue. By understanding and prioritizing product stability, product managers can build reliable, user-friendly products, and solidify their reputation as effective product managers.