A judgment only lasts for 12 years. After that it is not enforceable. Mostly people will have all forgotten about it anyway BUT where there was a Judgment Mortgage for instance and even though the debt is no longer due the Judgment Mortgage needs to be cleared from title if (e.g.) the property is being sold. Now, while technically the debt is no longer due, if there is an urgency ( these things only ever seem to come to light on closing day with everyone poised and ready to go) the creditor could decide not to co-operate until the debt or some portion of it was paid.
Plus the debt may still show up somewhere and even though it may be more than 12 years old, the fact that it has not ever been paid may , just may, affect credit rating.
mf