Why is Antimicrobial Resistance the biggest threat to humanity?

In 1928, at St. Mary's Hospital, London, Alexander Fleming discovered penicillin. This led to the introduction of antibiotics, which has since shaped human history. However, like many times in our human history, our boons have been exhausted to the point where they turn into banes. The growing issue of antimicrobial resistance (AMR) is one such classic example where unsustainable practices are leading to a human-induced disaster.