You can be a technically excellent dancer and still be the person nobody wants to partner twice. The social floor runs on a set of courtesies that rarely make it into a lesson, and picking them up early saves you a lot of quiet rejection.
Ask, and accept a no gracefully. Extending a hand or a clear invitation is the norm; so is the absolute right of anyone to decline without giving a reason. A no is not a verdict on you as a person, and treating it as one is exactly the behaviour that earns a reputation. Thank your partner at the end of every dance, always.
Dance to your partner's level, not your highlight reel. Leading a nervous beginner through your flashiest combinations does not impress them; it overwhelms them and often hurts. The mark of a strong social dancer is making whoever is in front of them feel good, which sometimes means doing far less than you can.
Mind the floor. Social dancing is a shared space, and a spin that flings an arm into a neighbouring couple is your responsibility, not theirs. Keep your patterns compact when the floor is crowded, apologise if you clip someone, and keep an eye out the same way you would in traffic.
Finally, look after yourself and others: fresh shirt, breath mints, a light touch rather than a grip. None of it is complicated, and all of it comes down to the same instinct that makes the dancing itself work — paying attention to the other person. Get that right and people will keep saying yes.