My theory on the female orgasm is this: Many people are lead to believe that a female orgasm is like that of the males. While a male may be able to 'stay hard' for several minutes..thus putting the orgasm on hold, giving them the ability to stop, the female body can do no such thing. There is no stopping when giving a female an orgasm. A metaphor I like to use is that when giving a female an orgasm, its like building blocks. You build a tower of blocks..but when its knocked down, you have to start all over again. When you stop touching a woman and shes 'building up' the feelings of an orgasm, you knock the whole tower down. Only until that last block is in place can you push it over. So to any of the unexperienced out there..take this into consideration.
An after thought as well...by simply having sex with a woman, i.e. the act of putting ones penis into a womans body, you arent doing much for the woman. It does feel good to an extent, but if you want to make sure she has an orgasm, you need to do a bit more work than that ;) This of course is just my opinion...

I've just recentely found seven facts about the female orgasm that I thought would be a helpful reference.
They are as follows:
1. All women climax differentely! For some it is the stimulation of the clitoris, for others the infamous 'G-spot', and for others still, both!
2. Orgasms don't (pardon the pun) come easily!
3. Our partners need pointers on what turns us on! They won't automatically know what to do, so show them!
4. Intercourse, alone, doesn't cut it (at least for most of us)!
5. Not all orgams have the same oomph! We can't always expect an intense orgasm.
6. The mind has more verve than a vibrator. We really have to 'get into the mood' in order to enjoy sex (men, you could help out here). Our mind will wander if we let it!
7. Orgasms aren't proof of good sex!