Is there any point of asking a girl if you are good looking ? Should guys ever ask this in general ?

It's been shown in studies that females only find 20% of males to be above-average physical attractiveness. That's kind of insane, mathematically wrong, but that's the kind of statistic you find in fully polygamous animal species. It means that basically every woman who isn't a perfect 10 thinks she's settling. Guys, by the way, accurately judge women's looks such that 50% are considered above average.

What this means, practically, for guys, is they need to attract women by way of things other than looks. It also means that guys should really never ask their girl if they're good looking. It will only remind the girl she's (in her mind) dating down, it will hurt the guy's ego, and it will also also make him seem even less attractive to her by appearing insecure.

What this means, practically, for girls, is they need to be basing their relationships on things other than their attraction to guys (such as shared values, a desire for stable families), because if they do there's simply not enough guys to go around unless we go to a polygamous model. Most societies seem to have dealt with the issue by culturally enforcing strict monogamy, to create more social cohesion, and prevent the issue of lots of frustrated guys going around causing trouble. The recent breakdown of the traditional family in the western world is doesn't really bode well for long-term societal stability, but perhaps enough girls and women will realize they're better off "settling" for "below-average" males lest they simply end up in harems treated like interchangeable property by the top 20% of men.

I feel like you sometimes shouldn't but I have and it has worked out. I have felt insecure a few times in my life and I asked my ex what's her honest opinion on me and she's says I am a good looking dude which did make me feel better

Everyone has a different view of "good looking" ... so what one person thinks is not necessarily the next person's opinion.

Anyone asking anyone else if they're good-looking shows insecurity and desperation. It doesn't matter what your sampling of girls might say about how you look because another group would say something totally different. Beauty is in the eye of the beholder and as a hetero male you've got the advantage that women aren't as visual as men and aren't as likely to overlook you just because you're not physically "hot". So work more on the personality and worry less about how you look.

NEVER do that ...reeks of neediness / no confidence

Never. It sounds absurd

I can only tell you that they don't. As innocently as you put it there is nothing wrong with it. But how about the delivery? You could only ask this of a sisterly relationship.

never. Shows lack of confidence

i will think you are some kind of retard..:'p