I was wondering the same thing yesterday. I stopped by Mr. Ned's yesterday for a fitting and they showed me that the support in the lapels is different between a 3 button and 3/2 or 2.5 roll. There's a heavier strip of material that runs along the length of the lapel canvas. It determines where the lapel will naturally break vs. ironing. If you just iron it it will at some point want to return to its natural break so it's best to have it made correctly in the first place.