Many times, and indeed in most cases today where a defendant does not need to be put in prison immediately, an individual who has been convicted of a crime will, as part of their consequence/punishment, be placed on probation (or parole upon their release from prison).
In every case, one of the conditions of probation and parole is that the defendant is not commit any new criminal offense, and to follow and obey a long list of rules. Committing a new criminal offense or not following the rules is a violation of one's probation or parole. As a consequence for violating the terms of probation or parole, the defendant's probation or parole can be revoked and the defendant sentenced to serve time in custody.
It is well known that in a new criminal case, the defendant can only be found guilty of committing a crime if the prosecution proves each and every element of that crime beyond all reasonable doubt. But, what is the burden of proof for the Government to be able to revoke a persons parole or probation? It is not by the same high standard of beyond a reasonable doubt.
Rather, the State only needs to prove a violation by the civil standard of proof of "by preponderance of the evidence" that a violation was committed for the probation or parole to be revoked. Preponderance of the evidence means "more likely than not." If beyond a reasonable doubt means you are 99.9% sure then preponderance of the evidence is only 51%.
Therefore, because the burden of proof is different, it is possible that a defendant could be found not guilty of the new offense and still lose the probation or parole violation hearing!