Why do someone else hold the Thaali when the groom ties it?

Maapila thaali kattumbodhu kootama oru 4 peru ilana orthar atleast en thaali ah keela pidichurkanga? Enna significance, enaku annoying ah iruku aana seri edho sola varanga pola nu vitute. Can someone explain why. Is it really necessary? Adhaan bride pidichukrangala?