Also, it protects the private keys that can validate transactions on these accounts. Instead of ETH L1, where accounts and private keys are ideally the same things, StarkNet supports account distraction, which means that each account is an advanced contract that should be installed before interacting with the network. This is an added complexity and an amazing opportunity for a regular user.
Thankfully, Argent X Wallet abstracts each complexity for users: it generates and protects the private keys, installs account contracts managed by their keys, attaches to decentralized apps, and transfers transactions to a StarkNet network.