So that every service I use can have a randomly generated, unique password. Therefore if one of them gets hacked and my password leaked, brute-forced, or decrypted, it won’t affect any other service.
Plus it stores passkeys and handles 2fa code generation, keeping them synced on all my devices, and ensures I never have to remember specific passwords because they’re all safely stored in heavily encrypted vaults guarded by the only single password I do have to remember. Also it notifies me if any of my information is in any breaches, or if I could do better to secure my account.
Trust me when I say, it’s safer, simpler, and smoother way to manage things.