Why HTML cannot create dynamic output?

Answer 1

HTML cannot create dynamic output because there is no logic written into the language.

To make any dynamic output, the page has to be able to make decisions of one kind or another. For instance "Did you user click on that button?" or "Is the user's mouse over the image?"

The nature of HTML as a markup language means that it lacks these basic functions. Instead, a higher level language like Javascript is employed. Javascript has the ability to create if-the-else statements, for loops, and object oriented events. This means it can make those decisions, and act on them.