Why do wool sweaters actually go in case of wrong treatment?

Professional scrubbers is clear: wool is sensitive. Who does not pay attention and clothes made of high-quality, clean wool holds together, pouts, holds not infrequently after a child’s sweater in the hands. But what is the reason? The wool fibers are surrounded by a layer of dandruff that gets caught in the spin and shrinks the garment. Care labels make it clear which pullover is allowed in the washing machine and which not.