One intern showed me an issue he was facing. "Delete" button was not working in a HTML page he had developed, but edit button is working properly. I checked the code both buttons had same id "edit72-btn". I said to him you need to use unique id in a page.

The thing he said next made a speechless. I was just looking at his face.

He said "edit72-btn and del72-btn are almost same, couple of characters are different. Are they going to work?"