There's nothing amazing about it. Android and iOS work the same way. But people don't understand it, they still think an app they stopped using 10 minutes ago is somehow "running" and using their memory and/or battery and have a burning desire to "quit" the app or make it disappear from your recent app states you find when you hit the back button.
It's just a fundamental misunderstanding of how modern smartphones work and left over thinking from the days before modern memory management, i.e. Windows 95/98, Mac OS 9 etc.
It's going to be tough to break people in their 30s or older (I'm 39 for the record!) of that thinking pattern so I guess they might as well install a "magic button" that makes the apps disappear from their previous state since people don't seem to want to accept what is actually happening. I think people in their mid to early 20s have always known OS's that are competent at managing their own memory so they are much less likely to have this misconception that they need to neatly box up every app and "put it away" when they are done with it to save memory or battery or mojo LOL.
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