Why does the fancybox slider stop working if I change the a attribute to a div?

Question

fancyBox

Replaced attribute a with div

<div class="fancy "  data-fancybox-href="/img/2.jpg"></div>
<div class="fancy "  data-fancybox-href="/img/3.jpg"></div>
<div class="fancy "  data-fancybox-href="/img/4.jpg"></div>

and replaced href with data-fanvybox

With tag a, it scrolls when opened., with div no, it opens only 1 picture.