The choice of a NoSQL database is crucial for building online and operational applications, as it can significantly impact the quality of the user experience. To select the right database, one must define its specific function in the data pipeline, consider latency requirements, throughput needs, and the type of data being stored. Developers often choose NoSQL databases due to their ability to handle semi-structured or unstructured data with flexible schema, simple query patterns, high-velocity transactions, large volumes of data, and quick scalability via distributed computing and storage. The CAP theorem can be used to prioritize characteristics such as consistency, availability, and partition tolerance, helping determine the best fit for an application. Additionally, managed services solutions and self-hosted options are available, with benefits including reduced maintenance, increased scalability, and improved performance. Ultimately, selecting a well-thought-out NoSQL database choice is essential for delivering instant experiences and meeting user expectations.