Leap Motion generated hand/finger is untagged. Reason?

As I you can see from the attached image, I have created a prefab of a hand (that is actually holding a gun).

I am only mobilizing the index finger and I would like to trigger a box collider with IsTrigger=true, and I only wanted to trigger this with the finger tip of my index finger.

So I attached a tag to my bone3(the fingertip bone) called “Triggerable” .

However, when I was writing code for OnTriggerEnter, I realized nothing was happening.

So I wrote a test Logging code

    void OnTriggerEnter(Collider other)
        Debug.Log(string.Format("{0} | {1} | trig", other.ToString(), other.tag.ToString()));

And realized that my bone3 was losing the Triggerable tag.

What is the possible cause of it?

Bit hard to see from your hierarchy, but it looks like tag is not on the same gameObject as the collider. What if you try testing/logging against other.transform.parent.tag instead?