You don't know your customers

Product managers are responsible for the product strategy and making sure the product meets the needs of the customers. In order to do this, product managers need to have a deep understanding of their users and what they need from the product.

However, many product managers make decisions based on their own beliefs and assumptions without actually speaking to users or collecting data about their needs. This can lead to products that don’t meet the needs of the users and are not successful.

To be a successful product manager, you need to be data-driven in your decision-making. This means looking at all available data about your users and their behavior, and using this to make decisions about the product. It also means speaking to your users directly to get feedback about their needs and what they want from the product. A/B testing can be a useful tool in this process, but it should not be the only thing you rely on.

Ultimately, being a successful product manager means putting your users first and building a product that meets their needs!