Why is there no blinking reflex when touching the outer eye?

There is no outer eye. There is simply an eye or the outer apex of the eye. If they touch the eye, then we reflexively close it. But if they touch the outer top of the eye (the corner where the eyelids join), then the eye will not close, since there is no danger in such actions. If a person’s reflexes work well, then when a foreign particle enters the eye, its reflexive closure and the release of a tear begins in order to remove this particle from the surface of the eye. If this does not happen, you need to use special drops.