A thought occurred to me, recently: Can a WAM fetish be "learned?"
For example, a 20-something guy is perusing the net, and he comes across a mud-covered girl. He's never seen anything like that before, but he finds the photo strangely erotic.
Or perhaps, a married couple attends a poolside cocktail party, one evening. During the evening, the wife ends up in the pool with her dress on. He's never seen her wet with her clothes on, and he finds this very arousing.
Personally, I think this might be possible. What do you all think?

None of that is "learned". It's all examples of discovered.

I agree with Noise. These are examples of dormant fetishes coming to light for the first time.

A better example to reflect the original question might be: a guy who isn't into WAM has a girlfriend who is, and she asks him to mess her up and just keep an open mind, so he plays along to keep her happy... Then they break up, but he carries on getting messy alone and wants to introduce subsequent girlfriends to it, as he learned to love it when his girlfriend first introduced him to it.... Could this happen and would it evolve into a full blown fetish?

I guess "learned" was a bad word choice. What I mean is it's a dormant fetish some guys have that comes out when they're exposed to it for the very first time. For most of us, it's during childhood, or in our teens, but maybe for some guys it only comes out later in life.
Yes, Labryinth's example would be more "learned.

I'd say there's no doubt that's possible. Granted, I've been quite aware of my wam fetish for a /very/ long time (witness that I joined this site in May of 1998), but there have certainly been other fetishes I've only become aware of as a result of discovering images of them online, chief amongst these being watching exhibitionists. (I say 'watching exhibitionists' rather than 'voyeurism' to specify that my pleasure comes from watching people who are willingly being seen in a sexual manner in public, rather than the traditional definition of voyeurism which presumes that the voyeur is observing someone without their knowledge.)

As for 'learning' a fetish, actually, I think that's possible as well. I was completely unaroused by electric shocks, to give an example, until I encountered them in a sexually-charged (no pun intended) environment as I was exploring BDSM. Initially, I simply ignored electric play even when I did encounter it, but eventually the joyful noises coming from the electric bottoms at the play parties I found myself at led me to experiment with topping and bottoming to that form of play. Initially, this experimentation yielded no pleasure to me, but eventually, this changed. I found myself more and more aroused by the reactions I could elicit from my partners with skillful application of electricity. Over time, I've come to the conclusion that this is my second-most-intense kink, right after wam itself, but this wasn't a matter of discovering what was already there. It was a matter of learning to enjoy something I previously had not.

I discovered it after my bf "came out" to me about the fetish.

I thought "wow, how can that possibly turn him on"

Well we tried it in the bed room a few times and I was surprised how fun it was.

Then some thing happened. When we started doing scripted shoots the more humiliating scenes started to turn me on.

In fact in my "pie day" shoot below I got really wet and after we cleaned up I told my bf that I wish he would have just fucked me right then and there in all the mess.

He was like "why didn't you say anything!"...lol

Wrong. You cannot speak for everybody.

My ex-wife "learned" it. Became a huge fan of it. Not sure if she still does anything now, though.

I also had an ex after her who was really into piss play. I played along because why not? But by the end I did find it turned me on a lot and would totally do it with someone else.

Most of us here were born this way. But it can also be learned through conditioning and experience.

I actually think that those who discover it later in life have different preferences than those who have had it as long as they can remember. I have had a pie in the face fetish since I was a little kid -- really! I remember watching shows in the early 1970s and when a girl would get pied I would feel flushed, etc.

So how does the difference between lifers and late-bloomers manifest? I like situational WAM and actually prefer clothed WAM (if only because when the clothes come off it becomes overtly sexual in a "porn" way and I don't care for that -- still will buy it, but prefer if it is not the focus). I think this is related to my early experience in seeing WAM on variety shows, etc. For me and other lifers, it might be that WAM is more wrapped up in early experiences that are not clearly connected to sex. People who discover it later -- like maybe through this site or through a partner -- are more likely to have a preference for more overt sexuality in their WAM (i.e., nudity, sex, etc.)

Just my two cents.

No, you're wrong, and I'm not giving you any reasoning either.

Well, for me, I'm a lifer; WAM has been my thing since I was only 2 or 3 years old, however, I'm also a fan of overtly sexual WAM too.
Not that I'm against seeing clothed women getting messy or doing the same in my own sessions (it's all good!), but for me a large part of the arousal is in the physical sensation and that is experienced most intensely when the mess is in contact with bare skin. Primarily the clothed WAM I enjoy is that which centres on enhancing that sensation (i.e. underwear/swimsuit filling).
...My fetish has always been there, but the girls I've got messy with who have enjoyed it didn't do it because it was their fetish, but simply because they found it fun and breaking taboos etc, which felt naughty so it turned them on. I'm the same with anal sex - it's not a "thing" for me, but I sometimes do it because the naughtiness of it is appealing and arousing. I think this psychological state of being naughty, partaking in a fetish that is not your own, is probably quite common and very easily "learned". However, whether something is a true fetish or not is still open to debate.
For me, being into WAM is like other people being gay... it's just the way I'm wired, from the outset - always has been and always will be.