In all my years of travelling for work, I've stayed in many hotels and I reckon that, in about 5 per cent of those hotels, there's been a light somewhere in the room or suite that I simply haven't been able to turn off.
In my efforts to get to sleep, I've unplugged bulbs, and even called for help from reception to get a darkened environment. Sometimes it'll be a bulb that's not directly shining into the sleeping area, so I can ignore the light altogether. But it can be a stressful affair, hunting for the right switch in what should be the final restful moments of the often-tiring days of travel.
Here's a hot tip for the people who design hotel rooms: Make sure there's a switch immediately adjacent to every light. It might not suit your architectural vision — tough. The guests don't care about your fancy theories of feng shui — they just want some shut-eye.