In cases involving divorce, child custody and child support, court orders are not always followed in some way, or even not at all. The aggrieved party must then bring this to the court's attention in order to seek that the order be complied with. This is done with a "contempt motion".
Someone charged with contempt of court can defend themselves if they can prove that they were unable to comply through no fault or action of their own. (For example, the person has no assets to satisfy the judgment and that person did not purposely waste or dispose of their assets.)
The court can jail someone found in contempt until the person complies with the court order, and/or assess a daily fine until the judgment is performed, as well as order attorney fees, in order to bring about compliance.
Cynthia Fox has extensive experience using contempt motions to bring about compliance on her clients' behalf.