The number one most-wanted person (by a particular sheriff) is a man who didn't register as a sex offender. He may have done something bad to be labeled a sex offender; it is hard to say.
It is hard to say because prosecutors have the power to pile on with exaggerated--even false--charges against someone in order to force them to plead guilty to something. Faced with charges that will result in decades-long incarceration, the defendant usually pleads to a lesser charge that means a shorter sentence. So when I see that someone has been charged with something shocking, I tend not to believe everything I read. And since such a small percentage of cases actually go before a jury, the prosecutor never has to prove anything.
Back to the most-wanted list. Let's say this man did something awful to be labeled a sex offender. Is it right that failing to register can put him back in prison with an additional felony on his record? Felonies used to be serious crimes; failure to register amounts to incomplete paperwork.
Should failure to register be considered a serious crime that sends someone to prison? If registering as a sex offender has been shown to prevent an offender from committing new crimes, maybe it should be a serious crime. After all, we want to protect people.
That isn't true, though. The recidivism rate for sex offenders is the lowest of any type of crime except murder. We cannot simply assume that he will go crazy out there with new sexual offenses. If he is the type to do that, will registering prevent him from new offenses? No.
I decided not to link to the sheriff's site because I don't want to help them find and punish someone for something that should not be a crime. Check the most-wanted lists for your own area; I would bet this is not an isolated instance.