For four years since I moved into my current apartment, I have had to listen to the horribly loud ventilation fans in my bathrooms whenever I turned the lights on. I have no windows in the bathrooms so the fans are definitely needed and I appreciate them when I take a shower. However, there was only one switch and it turned both the light and the fan on as one.
Most of the time I really did not want or need to have the fan on. I was so happy that my maintenance guys were willing and able to separate out the connections and put a controller in that had separate switches for the lights and fans. Sometimes the simplest things make me so happy!