When a user clicks on an element it triggers the onClick event of that element, and every parent element up the DOM. This is normally fine as it's rare to have a click on an element who has an ancestor with a click event too, but on those rare occasions where there is an ancestor with a click event it can be the most annoying thing ever. The last thing you want is to prevent the user from interacting with a button because it also triggers some other interaction. This can be stopped in many ways, but thankfully there is an AngularJs way to do it.