I agree with Amber, Aussienic and others - it doesn't have to be poor attachment to hurt.
For most people, if you are attaching correctly (and get some good, thorough advice about this before you leave hospital) then the pain will be minimal.
I had read books, been to classes etc and done all that...
but unfortunately, I was one who had perfect attachment and VERY painful nipples (blisters, cracks, bleeding... I still have very deep scars to show for it!). I was seeing a lactation consultant regularly who assured me that attachment was fine and that it should get better soon. Well, it did get better... after about 3 or 4 months.
If you DO end up with sore nipples - I highly recommend 'Nipple Paint' - you have to ask your pharmacist to mix some up for you. I *think* (can't quite remember) it's cod liver oil and ferrous balsalm in a certain ratio. I tried the colostrum, air-drying, sun exposure, lansinoh, paw-paw ointment, bepanthen, you name it. But the nipple paint was what worked for me.