Is it ever optimal NOT to kill your lane opponent?
Usually withing the context of saving a summoner spell, and 1v1 in laning phase.
I understand if you're just beefing to the death and you don't need to burn anything then there's no scenario you don't take the kill.
and obviously if the jg might appear and get a follow up kill while the wave is at your turret then flashing to get the kill is probably a bad idea.
This is strictly in the 1v1.
I ask because when watching some high level gameplay I occasionally see times where they could 100% burn flash to finish off their opponent such as with kassadin flash ult combo to close a lot of distance and surprise them.
I might be misremembering but I even vaguely remember a top lane player say they were fine with just forcing the recall and not killing but I'm not sure why.