The purpose of the thread is pretty much the title, but I'll be a little more thorough.
How would you define winning an argument, or do you even define it at all? Do you expect to win an argument? Do you hope, or seek to? When you decide to engage in an argument, what motivates you to do so, and what makes you decide to end one? What do you expect to have gained when it's over?
I have my answers, but I'll hold off because OP answers have a way of shaping threads.