[Theory] I've always failed to see how "Narcissism" is negative

[Sassy Doll]

Apparently, "thinking that you yourself are on the right path" is bad.

To me, you are supposed to take decisions at all times which are the best ones you can make.

So ipso facto (by definition), you will think that you are on the right path. Because you deliberately chose the way you did.

Therefore only douchenozzles use Narcissist as an insult