I think it's a terrible UX the way it's presented, but there is definitely a use-case for the functionality. Say you have a modal that contains a step-by-step

I think it's a terrible UX the way it's presented, but there is definitely a use-case for the functionality. Say you have a modal that contains a step-by-step process. Now you can load multiple modals, and dismiss them one at a time. To a user, it will look like s/he is moving through the steps. Is this a good use? Ehh...maybe not, but it's possible. Just brainstorming here.