I disagree with the majority of opinions here. First the question isn't about record keeping but of society labeling someone who has completed all the requirements necessitated by the court system. The issue here is more about the dreaded box on initial job applications. Checking the "crime " box will in most instances get your application discarded.
Should the applicant be required to reveal his record in subsequent interviews, of course. Part of the reason we have such a high number of people returning to crime is that they never get a chance to explain nor show their qualifications in the first place.

re·cid·i·vism
/rəˈsidəˌvizəm/
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noun
the tendency of a convicted criminal to reoffend.
"the prison has succeeded in reducing recidivism"

This is why the keep records because many repeat their crimes.

If a person were to commit a crime in one state then move to a different state where no one personally knew them then they committed the same crime again then they would get second offenders treatment if there are records kept nationally as in the F.B.I. crime record service.

They were convicted. They are now ex-convicts. They are labeled felons to divide them from the non felons. Got it?

If your spouse cheated on you and you forgave them for it, would you forget it had happened?

Would you want a convicted child molester babysitting your kid? He served his time!