Why do some strain of bacteria and viruses develop resistance?

Question

Why do some strain of bacteria and viruses develop resistance?

In: 2

Answer 1

Imagine you had a Petri dish with a few hundred million bacteria in it, then drop in a weak anti bacterial substance.

Some die. Some don’t. Those that don’t then multiply. If they survived because they are more resilient then then those that come after are more likely to be resilient.

Now rinse and repeat