Baby teeth are more susceptible to decay because they are less mineralized and have a less organized crystallin structure.

“baby teeth are less mineralized and the crystallin structure is a little more haphazardly arranged it's not quite as organized so instead of like Lincoln Logs lined up it's more like Pickup Sticks to some degree why is that baby teeth are meant to resorb dissolve and fall out okay so this is why baby teeth are also much more susceptible to Decay”