Not sure then. I don't see that. I’m assumed there’s no chance you could roll onto home button/power button, activating Siri briefly? It doesn’t even have a 1m listed against it so that's weird! Report as a bug, maybe Apple can explain - or fix it. I don't know if perhaps everything in the Siri family (like suggestions etc.) come under that one banner and it's a brief bit of background work to prepare that.