Not true, all votes count even for convicted felons. When those rights are restored varies by state. In some states, voting rights are restored immediately after release from incarceration, some states require the offender to be off of parole to be able to vote, some states require the offender to be released from all forms of civil restraint I.E. house arrest and probation. There are a handful of states that depending on the crime require the offender to petition for voting rights to be restored.