There's nothing really wrong with this on one level. Your event loop doesn't even have to loop, it can just start by running your main and end when that ends. Imagine starting a server which has a while true loop that waits over a socket, and on some shutdown condition or interrupt ends, ending the program. No busy waiting, no messing with sleeps or sockets from the event loops perspective. Run until complete vs run forever.

Better off, if making some toy loop, to not bother with the forever case.