Which testing technique is most effective in uncovering missing functionality?

Exploratory testing is particularly effective in uncovering missing functionality because it allows testers to engage with the software application in a free-form manner, utilizing their intuition, creativity, and experience. Unlike scripted testing techniques that follow predetermined test cases, exploratory testing encourages testers to investigate the application more like end-users, which can lead to the discovery of functionality that may not have been explicitly documented or envisioned during the development phase. Testers can adapt their approach based on their findings in real-time, which often reveals gaps or untested areas where functionality might be lacking.

This technique not only emphasizes the tester's insights and adaptability but also enables them to explore the software's features holistically, which is vital in identifying missing functionalities that could affect user satisfaction and overall system integrity.