The tales in Ovid's metamorphasis all share on thing in common, the theme of changing. Sometimes a person is changed into a beast, while at other times a man may be changed due to blood on a piece of clothing. In some way through out the tale a transformation occures within the characters. All these things seem mythological, however they seem to be a metaphore for the real reactions of humans.
In Actaeon, he is turned into a stag for viewing Diane naked and bathing, quite literally he becomes horny. Is he not like so many young people, men and women, viewing that which is forbidden. No matter how wrong it may be, or how detrimental it may be to us, we are still drawn to it. Is a part of us changing or are just acting on our baser instincts. Perhaps part of what draws us to these things which are forbidden is the fact that they are forbidden, and against the rules, and perhaps for a brief fleeting moment, it feels right, and good, and we want to continue upon this course. Our baser instincts that lead us, are the "animal" in us, much like the stag that Actaeon is turned into. We continue upon these paths only be lead to a place that brings harm to us. As beasts we are torn apart by the beast within us, and the beasts around us that continue to hunt that which is forbidden, mayhap the warning in this particular tale is to not be held captive by the beast within us, no matter the small gratification it offers.
Changing almost seems to offer a way out, by saying that it is not our fault, that we were over taken by something that which we cannot control. If all the characters made excuses for their transformations would that make them less valid? I believe so, because with each new transformation is another person behind it, and as such blame can always be placed elsewhere. I think maybe it is time that we stop making excuses for the actions and "transformations" that happen within us. Maybe then we will learn the lessons quicker and without so many pitfalls.