How to run script execution after AJAX

I will try to guess.

You add the hover event immediately after building the DOM tree ( $(document).ready() ). At this moment, an element with class="box animated" does not exist in the DOM tree yet.
As a consequence, the event is not assigned to it.

So you need to assign an event to the .box.animated element after it has been loaded into the markup. This can be done through JavaScript . But! It seems to me a cleaner approach - to make animation via CSS :

 .box.animated:hover { /*Тут пишите те стили, которые содержал класс .bounce*/ } 

UPD

If you really want to use the JS tools, then this:

 $(".box.animated").hover( function() { $(this).addClass('bounce'); // Добавляем класс bounce }, function() { $(this).removeClass('bounce'); // Убираем класс } )}) 

It is necessary to execute in ajax request callback, and not in document ready callback.

The $.ajax (If you do not use the promise model), the success field was responsible for this.

 $.ajax({ ... success: function() {/*Тут назначаете свой ховер*/} ... }) 

Hopefully I could explain

UPD 2

I understood, you have not Jikverai adjax, but endless scrolling. Try to assign an event like this:

 $(document).on("mouseenter", ".box.animated", function(e) { $(this).addClass('bounce'); }).on("mouseleave", ".box.animated", function(e){ $(this).removeClass('bounce'); });