Some cars get stuck at intersections forever for no apparent reason

Sometimes cars get stuck at an intersection through multiple light cycles even when it seems like they have a clear path through the intersection. This issue is particularly bad at the intersection of MLK and Graham in Seattle. It is likely caused by the small one-car "intersections" here over the train tracks. However, the intersection seems to be blocked even when there isn't a car trying to take a left from Graham onto MLK.

Realistically, cars shouldn't be able to "stage" for the intersection on the railroad tracks. That area should be considered part of the signalized intersection somehow, so that it is only open when the surrounding signals are green and all cars have to clear before it is blocked again.