@Edent usually it would tell you why in the log. It not having a reason (an action triggered by a person or an automation run) suggests the light itself or the hub it’s connected to triggered it.
@Edent sounds as good a reason as any. At least it’s not a device you wrote the firmware for so you can just shrug rather than knowing ultimately the blinding light at 3am is your own fault [gives the side eye to his bedside clock]
@Edent I think posting this cursed me as I was woken in the night by my bedside clock turning all its LEDs on while mysteriously no longer displaying the current date and time. (It is still receiving updates on the current cost of energy though)