Ok we use subflows frequently as a sort of multi-node "function". Some require input, others don't (they generate their own input instead).
Of course you COULD trigger a message if you wanted to with inject node, set a timer every minute or once on deploy. But that makes it extra hassle to add, configure, then remember to remove when done. All of which would be solved by a simple button. That so many nodes already have. Like inject (without input). Or cron-plus (also with input).
Having the option of both left-button AND right-button would be even better. Toggle debug or other dev/debug logic inside.
I get that this is not necessary in majority of use cases. Still, it would be super useful in more cases than I can count.
