Your coins are not on the device itself, they are tracked on the Blockchain. Your Ledger hardware holds and protects the private data useful to access and manage them. These data (private keys) are the certificate of ownership of your coins: they give full access to these coins.
That is why the 24 words you have copied on your Recovery sheet when you initialized your device are paramount: they are the backup passphrase to import these access data in any wallet, they give full access to your coins.
But without these 24 words and without your PIN code, not anyone can access your wallet, even if your Ledger device gets stolen. Your secrets are securely stored inside the Secure Element of your device, your coins are safe.
