I don’t think that’s necessarily the case for many women.
For countless generations, it was drilled into women that the man makes the first move. (I even remember being told that the first ‘I love you’ from a man shouldn’t be taken too seriously; but the second might be real...)
It takes a long time to get taboos like that out of consciousness.
My experience is that about half will play hard to get. The other half will drop hints, sometimes very obvious ones, and wait for the man to take the bait.
A very few times, I had women come on to me directly. This was the exception to the rule. I think in most cases they were inebriated or looking to dish out relationship revenge to someone else.
One very sure sign that a woman is into you is if she offers to pay for something, like food, drink or entertainment, without being prompted. This is rare and falls into the indirect category. I have never found it to be wrong, however.