In Reply to: they also posted by dccc on Friday, 31. December 2010 at 11:27 Bali Time:
The seatbelt sign is controlled by the flight deck, and the cabin crew often have no idea when it will be turned off, as its the captains call.
Often the captain will turn it on if there is no turbulence at that exact time, but he can see up ahead the opportunity for it to present itself, so he turns it on for the crew & passenger safety.