I never received enemas growing up.
But I have given many, many, many disciplinary enemas (and received a few). Generally I combine them with spankings.
I think MOST of people's fears of disciplinary enemas (except for pain... they're far easier to bear than spankings; even a mild spanking should genuinely hurt; while disciplinary enemas involve discomfort, genuine pain during an enema calls for stopping immediately) are founded. They're uncomfortable (enemas can also be erotic, but anything with the word "disciplinary" in it is going to be uncomfortable). They're intimate (though I once gave a young woman a weekly spanking and enema every Saturday for two years and we never had any other contact more intimate than a weekly fully clothed goodbye hug of comfort and support). And modesty is out the window. And, they take a while.
But I've found them EXTRAORDINARILY effective for those who really need to feel subject to the authority of someone else. I've dealt with the paddle fighters... they might not even mean to, but they just cannot help but fight. And, I've dealt with those who just cannot surrender to the spanking. There's no fighting the enema. And, when having to retain an uncomfortably large volume of soapy water, causing uncomfortable cramping until someone decides you can release, there's just no pretending you're in charge.
From both ends of the nozzle (like spanking, 99% giving, 1% receiving), I highly recommend this as a disciplinary tool. While my experience (giving and receiving) has been primarily combined with spankings, I've found that it impacts some people far more quickly than does a spanking.
Of course, just my perspective~