Multi-Factor Authentication (aka MFA, 2FA or two-factor authentication, etc.)
It's pretty clear that I believe that you should be using MFA today, now, get on it! It's been around for years and most people don't know or don't care. Security professionals like me are yelling from the roofs that it's important but few are hearing us.
However, nothing is perfect. Included in the links is at least one article describing issues with two-factor authentication. Deadbolts and other physical locks are not perfect, either, but we use them because they do more good than not. Use MFA/2FA!