This surah protects you from something you cannot even see: whispers. Shaytan cannot force you to do anything at all. He can only whisper little bad ideas into your heart — "go on, tell a lie", "do not share", "skip your salah today".
His special name here is Al-Khannas, which means "the one who sneaks away". As soon as you remember Allah, he shrinks back and runs off — like a mouse when the light switches on!