The common use case here or the expected use case would be if you're doing something like talking to a whole bunch of network hosts and you want to return the results as they come in. You could use something like aio iter tools to then do things like batch up those results or run another coroutine across every result as it comes in, things like that. The other added benefit in here is that there's also a concurrency limited version of gather. So essentially, it's making sure that the event loop would never see more than 64 active tasks at a time.