If you look at it at just the right angle, you can see that it contains the shape of a woman lying on her side. (Whatever that may indicate when this line was drawn...)

A friend of mine spent a bit of time working on a road crew. They had that sort of thing happen when they were laying temporary lines or the guy running the main machine had it set wrong. With the temp lines, the lines are basically stickers applied to the road. If the adhesive doesn't set right, or the road is dirty enough to coat the adhesive, the lines can peel up.

With the standard paint machine, I guess it takes practice to set it that badly, but it can be done.