Have you noticed many more people are turning their signals on just as they are braking for their turn? Or pulling into the ‘left turn only’ or ‘right turn only’ lanes and THEN putting their signals on? It like it’s part of the rules to do it but people don’t really know what its purpose is. I’m not in your car with you so I can’t ask what you are planning to do. I don’t drive behind you every day as you drive the same route you’ve driven for years, so I don’t know you are going to turn there. Using the turn indicator tells me you may be slowing down ahead. That I should look ahead of you to see if anything will be forcing you to low down a little quicker. I can back off your tail a bit if I am too close. If you put your indictor on while braking, I am reacting to the brake and turn signal at the same time, it will be a bit slower of a reaction. If I’m behind you, I need to know you are pulling onto the ‘left turn only’ or ‘right turn’ only lane so I can make any adjustments to my driving. Once you’re in that lane, I know where you’re going.