It's a timer, yes - but if you do not have enough attention to see two RED lights on an otherwise empty intersection (one overhead and one right at your eye level), you have no business being behind the wheel, as you either a) are legally blind, or b) have the attention span of a proverbial goldfish.

The suggestion that anything important should be screaming and blinking (otherwise the poor driver couldn't have noticed) is patently ridiculous. There's quite a lot of other, less conspicuous things that a driver needs to be aware of (such as pedestrians or potholes).