Departure Information and the Critical "At Own Discretion" Phrase

Some student pilots misunderstand "at own discretion" as permission to take off whenever they feel like it. That is wrong. "At own discretion" means the station provides no clearance and the responsibility for safety is yours. You must still ensure the runway is clear and no traffic is on approach.

In practice, if you have monitored the frequency and heard no other aircraft, and if you conduct a thorough look-out scan, the runway is almost certainly clear. But the phrase "at own discretion" reminds you: you are checking, not the controller.