To aspire to a natural birth is not about looking to inflict pain on yourself, but looking for ways to reduce the fear that increases the feeling of pain and to use known methods for reducing pain without using medical methods that carry risks!
There may be pressure for women to achieve a natural birth, but whilst I think this is wrong in itself, I do believe that more can be done to help women have less medical intervention in some circumstances (not all by anymeans)
For me it was not a failed epidural, the epidural worked fine, but the consequences were still there (limited options for birth position leading to instumental birth with headache for baby, pain with catheter with had to be left in for 12 hours after birth). My subsequent births I was more prepared for mentally and both of them were wonderful, whilst not pain-free, I did feel in control of the pain rather than it in control of me.
For me epidural was definitely not as good as I thought and definitely made me think about risks the next time around. (having said that I would have tried a mobile epidural had that option been available to me on my second birth!)
My last birth I had no pain relief available (not by choice!), I got through with using breathing techniques and although one moment of panic and pain during transition, it was actually an exhilerating experience.
I look back to my first birth realising that my fear and panic at the unknown was part of the problem, if I had listened to what others were suggesting to me, I might have had a totally different first birth experience (which may have led to less pain for me and my baby).
It is not looking for a badge of bravery or taliban-like as suggested, the pain of the catheter and the tearing due to poor position for pushing did not make my epidural "pain-free", I chose to take another route with subsequent births, I was not looking for pain, but just using other methods of controlling the pain.