When is it necessary to automate a task in a website or javascript game?

So what I mean by “automate” is using a setInterval() to. well. you know: automate the task or multiple tasks. For example in a game you could use a setInterval() to automatically update a health bar or a stamina bar, and maybe on a website you might use it to update statistics (it doesn’t matter what they are). At what point does it become over-used or unneeded? and when would you need to have something like this?