Secret of Penicillin Discovery
Penicillin has literally been a lifesaver since it was discovered back in the 19th century by Alexander Fleming. However, he does not deserve all of the credit for the discovery because he was actually coming up short with his attempts to study mold.
He discovered it by accident, but the levels he was originally producing were insufficient for it to be of any use to anybody. Thankfully for him, along with the rest of the world, his assistant inadvertently came to the rescue.
One day, Mary Hunt brought a cantaloupe into the lab for no specific reason other than she had just picked it up from a shop. Upon cutting it open, Fleming saw that it was covered in a golden mold, and as a result of this examination, he discovered that it was a form of Penicillium that was able to produce over 200 times more penicillin than he had been able to do up until that point.
In other words, the millions upon millions of people that have been saved due to penicillin can give thanks to Fleming as well as the shop that was guilty of selling that rotten cantaloupe.