In the past I wrote that I believe that subs who crave humiliation do so because it "safely" exploits upon their deep fears and insecurities in a controlled way. That is, it proves their fears to be true without the pain of rejection. e.g. with SPH, a sub has the insecurity/worry that their penis is too small. When they are humiliated about it, their fear becomes reality but it isn't something so bad that they will be discarded. This can actually be a bit peaceful on some level, even if the feelings themselves are shameful since it avoids the worst case scenario, she leaves you for someone else because of it.
While working on fs01 I started thinking about a certain notion, namely, why is it that I keep introducing new characters every arc? The best answer I could come up with is related to this topic.
When it comes to humiliation, a logical view is that at some point being humiliated in the same way repeatedly should eventually "get old." Once that emotional pain is driven home enough times, their beliefs should adjust and accept things. If they truly believe it is the way that they are, there is no reason to be embarrassed anymore, right?
For some reason that doesn't seem to happen that way. For example, if a Domme makes her sub wear pink panties every day and calls him a sissy. Under that theory, there should be a time where it feels completely natural to him to exist in this state, so if she were to tell someone in his presence that he wears pretty pink panties, that shouldn't humiliate him much... but in most cases it still does.
I have two ideas in regard to this. The first is that in D/s couples where humiliation plays a large part of their dynamics, the Domme usually enjoys keeping the sub in a state of self-consciousness. Something you will find that is fairly common among Dommes that enjoy mind-fucking is that they often take a good deal of enjoyment in making a sub squirm due to emotional discomfort. Through this method, the sub is never truly permitted "comfort" from accepting their new truth: while they see it as true, it is also associated with shame.
The other idea flows from a bit of a different place, namely, the male ego. While humiliation has the power to crush the male ego, the ego never really dies... it only goes away for a little while. In this case the psyche continues to rebuild itself even after being broken down repeatedly and continues to battle against accepting the new "truth." It loses the battle every time but always rises to fight another day... only to be humiliated and crushed in its next defeat.
I'm not sure if either of these are wholly accurate, but they seem reasonable.