Well your suggestion doesn't really address anything other than one aspect of justice. We don't just incarcerate as a form of punishment, but for the good of society as a whole. Rehabilitation, incapacitation, retribution, restoration and deterrence (or some combination of these) are considered the philosophical justifications for incarceration.

Arguably, a repeat violent offender has established through their actions that rehabilitation won't be successful. Prior to 94, the felony recidivism rate usually went up with each felony. The concept of retribution in a 3 strikes state is that a repeated disregard for the rules of society is something that needs to be punished on its own. This is certainly the most controversial, and the one you seem have a problem with. Restoration is satisfaction for the victims of the crimes the repeat offender committed. If you are the victim of a repeat violent felon, you want there to be a harsher punishment for someone who has consistently shown a blatant disregard of the law. In order to restore a victims faith in the justice system to keep them safe, they are going to want to know that someone who is consistently giving the middle finger to society is going to be punished.

However the real thrust behind 3 strikes are to incapacitate and deter. The idea is to deter a would be recidivist from continuing their felonious behaviors. The hope is that a person who would continue their behavior because "If I get caught, its only 2-5 and I could be out in 1" now has to weigh the more significant punishment for continued behavior. Incapacitation is the biggest factor, if you don't want to participate as a constructive member of society, we will not further allow you to hinder it.

Your opinion on the matter, while a valid complaint, has very little to do with how our justice system was set up. I started discussing 3 strikes as a devils advocate because I think there are some severe flaws. For instance you can get three felonies in the same night, despite never having been in trouble you could wind up with a life sentence. That to me, doesn't satisfy the spirit in which 3 strikes laws were written.

TL/DR: I thought it was clear I wasn't a fan of 3 strikes. That said, your response is a really narrow view of what the justice system is actually trying to accomplish.