A system and method for automatically adjusting a learning mode duration on a virtual computing instance for an application security system extends a minimum duration of time for the learning mode duration for a guest agent running in the virtual computing instance based on a condition with respect to suspicious activities and deviations from normal behaviors detected during a fixed time interval. The guest agent is switched to a protected mode when the condition with respect to the suspicious activities and the deviations from the normal behaviors is satisfied for any fixed time interval after the minimum duration of time.