Well I'm no longer single, but I did learn a few things along the way.
The biggest red flags for me are;
Comes on strong; For example, says I love you before she even knows me.
It's all about her; For example, demands I prove I am worthy of her time.
Is rude or insensitive towards anyone.
Demanding, has to have it her way.
Any of these is a no go for me, and I hope for any woman considering if a man is worth pursuing.
Building a good relationship is all about getting to know one-another. No one can be sure what kind of person they just met aside from any red flags that may be exposed.
A quiet man or woman may be shy, or uninterested. But a person who makes big promises right from the start is always a liar.
An honest man will never pledge his undying love to someone he does not know. Only a user does that.
A player knows how to appeal to a woman's ego, he knows how to play her, thus the title.
You may be a princess but he can't know that if he doesn't know you very well. It's as simple as that.