How am I not justified?

Justification cannot be earned or achieved through human effort or adherence to the law, as articulated in Romans 3:20, which emphasizes that by the deeds of the law, no flesh will be justified in His sight. This highlights the futility of relying on personal merit or works for salvation. The law only reveals our sinfulness, and trusting in our own righteousness leads to condemnation rather than justification. As Galatians 3:10 points out, those who rely on the works of the law are under a curse, reinforcing the necessity for grace through faith in Jesus alone for true justification.