But the "art" of flirting comes from being able to read people, understand what they are saying, and talk to them in a way they like. Not telling them what they want to hear, but talking to them in a way they understand.
Flirting doesn't have to be sexual in nature or lead to a sexual relationship. You can flirt with someone just to build a relationship.
Think of some "hot-shot-movie-celeb" .. all the "top" celebs flirt with the camera, they flirt with the interviewer (man or woman), they flirt with just about anything that moves.
Granted some of the celebrity flirting is a narcasistic personality disorder, but the principle remains that they get more attention or admiration when they flirt.
Now, why flirting versus just opening communicating?
Simple.
Flirting allows a type of flattery such that the other party will receive your words in a way they can enjoy, conversely, it allows you to feel out the other party in a way that you wouldn't be able to in a setting in which you're both just "talking".
You don't _always_ have to flirt. You don't always flirt with your significant other because sometimes you're talking about things that need to get done. But after the fact, you might flirt a little to lighten the mood or to put a mind at ease.
It's not butt-kissing either, so don't send the wrong signals.
Flirting has gotten me further than any other soft skill with regards to human interaction, and I generally regard human interaction as a chore in the best of times, and my sardonic tones typically show that to be the case, but when I "flirt" (at least get my mind in that "mode"), my ability to connect and get real work done goes exponential.
Worst case scenario, you get a few advances that will go unrequited.