I was diagnosed with a serious case of scoliosis last week at age 35. I'm 5'2", 106 lbs snd have spent my whole life working out, especially loving being physical with my two children, everything from monkey bars, to dancing, gymnastics, kick boxing, skydiving, riding western rodeos. I also have spent a decade lifting weights. After my diagnosis I realize I had to change my shoes (and lifestyle) and have more support and comfort versus heels. Upon unboxing for the first time I loved the feel on my foot, however,  I couldn't figure out why I was sliding around so much in my living room. Well one look at the bottom shows you it looks like the shoes have been worn before and maybe someone stepped in something that made them slippery? Amazon says their shipping me a replacement pair so I will update my review once I've had a chance to get my new pair and walk around and review the bottoms of them to see if it's an integrity issue or they were worn before.