Deleting nearest index doesn't always work?

There are 3 objects in the scene. All are subdivided. “A” is the longest one that is suppose to get one of it’s points, closest to one of “B” or “B_2”, deleted.

For some reason, it doesn’t always work? B_2 works, but B is getting ignored? When I move slighly B in edit mode, it registers again. But it’s unreliable.

Does anyone know how to make it work all the time?

Nearest node doesnt always work.blend (1.1 MB)