What is the key characteristic of exploratory testing?

Exploratory testing is defined by its allowance for tester creativity and prioritizes the tester's experience and intuition. This method does not rely on predefined test cases or scripts but encourages testers to explore the application freely, investigate functionalities, and leverage their knowledge to identify defects. As testers navigate through the application, they can adapt their tests based on observations and findings in real-time, which can lead to the discovery of unexpected issues that structured testing might overlook. This adaptability is a hallmark of exploratory testing, focusing on learning and verification simultaneously rather than strictly following a formalized set of steps or requirements.