re: OT Doctors- Why do we become immune to antibiotics?

B/c life will find a way.

Jurassic Park should have taught you this.

eta: the real answer. Bacteria have the ability to share defense mechanism genes with each other. Say you have a table full of bacteria and wipe out the whole table with a certain antibiotic. Soon a bacteria will mutate with defense mechanisms against it and take over the table no matter how much antibiotic you throw at it.