A friend of mine who's a civil engineer says its because the freeway exits are a mile apart rather than 1.5 miles, so that creates a lot of very short merges an

A friend of mine who's a civil engineer says its because the freeway exits are a mile apart rather than 1.5 miles, so that creates a lot of very short merges and ramps up traffic heavily. What really gets me is the travesty that is 405 between renton and bellevue, feels like it should be 5 lanes but its only 2 full-access lanes and there's a crash every 4 hours because of how much the road bends suddenly.