Flaws

Oftentimes it's the people who have noticable "flaws" or aspects that can cause controversy, that gain the most attention on dating sites.

This is due to 2 main reasons. If someone thinks you're attractive and at the same time has "flaws" (that he or she may or may not find attractive) they'll be more incentivized to attempt to contact you. There'll be that idea of less competition.

At the same time, you might appear more unique. Some examples could be dyed hair, piercings, tattoos, etc.

Whilst there might be more people that find you ugly or less attractive, there'll also be more people that find you very attractive.

On the other hand, people who are universally considered beautiful might recieve less attention due to the subconscious idea that there'll be more competition.

You can also consider it as such; the average attractiveness of such individuals might be higher, however there might be less people that find that individual very attractive.