This is one issue that I have personally experienced myself. I was once told by a hairstylist that if I want to grow my hair long then I should brush it with 50 strokes every time I went into the bathroom. Needless to say, after about six months, I noticed severe thinning in the areas that I was brushing. Once I stopped, the hair eventually started to come back like normal. Unfortunately, I set forth in motion a pattern that caused my hair to grow back thinner in that area for the rest of my life.