What is A/B testing and why is it important?

A/B testing, grounded in the principles of randomized controlled trials (RCTs), is a crucial method for establishing causality and measuring effectiveness in various fields, including product development. By utilizing randomization, A/B testing mitigates selection bias and ensures that differences between treatment and control groups are due to the treatment itself, rather than external factors. This method allows companies to accurately assess the impact of changes, such as new features, on key metrics, as demonstrated by Recroom's experience of identifying a significant metric drop after a UI revamp. A/B testing reveals that a majority of ideas may not produce the desired outcomes, emphasizing the importance of measurement and iteration in development processes. Overall, A/B testing helps overcome human biases and errors in attribution, providing a reliable framework for making informed decisions based on evidence.