Longer piled or smooth piled carpets, such as velvets, show the shadowing effect quite strongly (think of running your hand down a velvet curtain). The same is true with a plain single colour. If you want to avoid shading showing too much then choose a mottled, flecked or looped carpet which can help to disguise it. Ask your retailer to help you look at the options if shading is something that will bother you.
It doesn’t affect the wear of the carpet and it is perfectly natural in both man made or wool carpets. It can not be prevented, no matter how good a quality of carpet you buy.
Shading is a temporary occurrence unlike Pile Reversal which is permanent and which we will cover in the next bog.