...that is sort of the question.
Scenario: I and a teammate are fighting a tough opponent who knows his class like the back of his hand and can easily handle a 2v1 situation. Teammate goes down, I'm still at a decent amount of health (but running out of endurance and most of my utilities are on cooldown), and the opponent is at less than 10% health. I'm pretty sure I can kill him if I throw everything I've got at him and then finish him off in the downstate, but if and only if I work at it, because this guy can kill me in two seconds flat if I lose concentration or fumble a keybind (which happens pretty often because I'm still terrible at PVP). I'm backed into a corner, so I can't just run away, recover health, and then run back. Teammate yells at me to stop shooting him and revive [teammate].
So the question is, what should I do in situations like that? Continue to try and kill the opponent? Or ignore the opponent and try to revive my teammate? Is it a case-by-case scenario?
(As for the outcome of that particular incident...I hesitated, trying to see if I could even get to my teammate without being instantly killed. Predictably, in the span of my split-second hesitation, I got steamrolled into the ground in a storm of multicolored pyrotechnics, and the opponent merrily strolled off, leaving two dead enemies and a captured point for his team. We narrowly lost the game...I'm pretty sure that was my fault. Sorry, teammates. That one's on me.)
fear not this night
you will not go astray