I know that Naomi Campbell wears wigs quite often because her previous weaves were very vicious on her scalp. Here is a photo of her hair disaster
This is why it is not good to wear hair extensions/weaves all the time. All the tightness and pulling is not good for the scalp. I know it can be difficult letting the hair grow on its own, but better that way than to have it lost for good in chunks.
Thank you, Steve, for this link of Denise van Outen and Melanie Sykes in rollers