Sorry, it does sound like “a bad mold will find new life with a hose clamp.” Not really the right message.
I pour my own one-shot molds. The bands are meant to keep the mold together if I have to “glue” it because I drop or jostle the mold. For small, uncomplicated items, repouring the mold makes more sense than taking a chance. However, if I’ve invested a bit of time and materials and creative energies, I try to salvage the mold and use the hose clamps.
Once it is in the kiln, I don’t mind if the band falls away because I’m a belt-and-suspenders kind of glass caster anyway. The bands “loosen” in the slow ramp up as the mold dries and the metal expands. The bands do their job which is to hold the thing together long enough to establish I’ve got a good repair, not much more.