[BZ_Zorro]

There's two reasons why:

1. The punishment part. People who show no remorse are far more likely to be repeat offenders. They lack the capacity to understand or care about the consequences of their actions.

2. The justice part. People make mistakes, and part of justice is balancing mercy with the need for punishment. People who understand what they have done, and feel true sorrow and regret about it, deserve some measure of mercy. A huge part of the seriousness of a crime is a viscious will, and courts must take this into account.