Uh Oh: The Army’s M4 Carbine Can Fire Even If You Don't Pull the Trigger

Its a problem of putting the selector part way between settings, pulling the trigger then moving the selector to a full setting ..
So, there is ZERO reason to do that on purpose, its mistake, not a need, trained, intended action, but a mistake on the shooters part.
That said, humans make mistakes and the trigger / safety group should have been designed to take into account human mistakes.

Whats the saying.. you cant make things idiot proof, because some bigger idiot will always come along and prove your design wrong.

See warnings on tide pods stating not to eat them.|
Read warnings on live electrical wires not touch them.
ect ect ect

It seems to effect the newest A1 version, but out of an abundance of caution all M4 service rifles are supposed to be tested doing a simple, user level function check.

Not a good thing to happen.

Yeah, all you have to do is move the selector switch.