When I ask a guy for something, I may get Yes as an answer half the time and No half the time. Yes mostly means Yes and No means No. If the answer is “Let me think about it”, that means usually that within 24 hours or so I will get a definitve Yes or No answer.
If I ask a woman for something, I rarely ever get a No. I may get Yes half the time and “Let me think about it” the other half. And moreover, Yes need not necessarily mean Yes, and “Let me think about it” ALWAYS means No – as in: I never hear about it again from that person.
On the surface, that sounds like dishonesty and playing games, and sure is inconvenient not to know what the real answer is. But I am aware of the deeper psychological reasons for not being able to say No to anyone, as I was once like that (and learned through persistence and hard work not to be). It is a matter of politeness mixed with a dose of fear (of being ostracized or something).
And it is certainly much more ingrained in – or inculturated into – women than men. How? Check this post and the 85 comments in the thread under it.