The bacteria Can Become Antibiotic resistant over time by adapting or evolving to them so new ones would have to be created to kill them. and this process just keeps repeating over and over.
Antibiotic resistance is a consequence of evolution via natural selection. Theantibiotic action is an environmental pressure; those bacteria which have a mutation allowing them to survive will live on to reproduce. They will then pass this trait to their offspring, which will be a fully resistant generation.