Reason 1. If the controller is out of order or malfunctioning, then it can get turned on.
Reason 2. Sometimes when Cortana do not understand something then it may turn on the Xbox.
Reason 3. It allows TV to control HDMI devices, so by just turning on your TV, your Xbox gets on.
Reason 4. If your instant mode is on then your Xbox never shuts down completely.
Reason 5. If you install and download an update, your Xbox gets on.
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