The speaker is captivating. You avidly take notes and agree with your neighbor that this is a great talk. You wish it could go on forever. But then it does.
Don’t let this be you. Your popularity will plummet with each moment you steal. People don’t want to walk out on you, and usually they won’t. But they may conclude that you have lost track of time, you didn’t plan effectively, you are in love with the sound of your voice, or worse, you don’t respect their time.
There are several solutions: Set a timer within view. Ask for someone to give you a time signal. Pack your talk with room to spare. Be willing to dump content if necessary. But DO end on time, and be the last to leave the room in case people want to speak with you afterwards.