When you try to pull out a sheet from a note book, a slow motion raises the entire book, But a sudden motion detaches the sheet. See the video below for a demonstration.

The paper get detached because of the inertia of rest of the book.

What is inertia of rest?

The inherent property of a body at rest to resist any change in its state of rest is called inertia of rest.

OR in simple terms,

The incapability of a body to change its state of rest by itself is caled inertia of rest.