I haven't ever faked if they aren't getting me there I let them know. I would rather tell the truth and work through it to show them what works for me and what doesn't then to lead them on thinking they are amazing in bed when they aren't
I never really understood the point of faking one. The reasoning of not wanting to hurt your partners feelings isn't even a valid one in my mind. Unless the G Spot is stimulated I can not cum from vaginal penetration alone I always let my partners know that and as long as I enjoyed the sex I also let them know that.
I don't lie about orgasm, but I will sound a little more enthused than I am to speed him along.
Now that I am a lesbian, I find that I do not have to do this as often as I did when I was having sex with a man. But motivating them with good sounds was as close as I came to faking it. I enjoy my orgasm too much to be a quitter for myself.
I don't think I ever have but my sister has admitted she has, but she has good reason because apparently her boyfriend gets really turned on when she orgasms so he gets more into it meaning sometimes the only way for her to actually orgasm is to pretend she already did.
I have faked it. Reason (simple): To get him off. Reason (complex): I was in a marriage with an emotionally abusive man. So for obvious reasons the thought of him even touching me turned me off. The only way to get him off was for me to fake it. Otherwise I would be ridiculed for not getting him off. It was pure self preservation.
Other than that, I have never faked it. I've never needed to fake it.