All Retra Flashes from the very first version stay powered on until they are switched off. This design comes from real use in the field, where a photographer may wait for hours for a single shot and prefers not to touch the strobe so the animal is not disturbed. Once the strobe is on, it continually tops up the capacitors so it is always ready to fire, and this naturally uses some battery power. With the 8xAA battery pack, the stand by time is around 24 hours, which is also stated in the data sheet. The trade off is that if you forget to switch the strobe off, it will eventually run the batteries down. We are considering adding a timer option for users who would like the strobe to switch itself off automatically. Thank you for your feedback.