There is something truly beautiful and even hypnotic about the rhythm of a wheel turning around and around in the truing stand. The rhythm is interrupted periodically by the need to stop the rotation, adjust a spoke's tension by turning the nipple this way or that; then the spinning resumes and the adjustment is checked. This start-stop pattern continues until the wheels is true and round again.
Some wheels take only a couple minutes of adjustment, like this one. Others can take longer -- up to a point.
Sooner or later, if the adjustments don't hold or spoke nipples are frozen with rust or corrosion, then you have to decide if the wheel is worth saving -- either by stubbornly wrestling with it, or by cutting the hub out and lacing it into a new rim.
But that decision generally only affects the most expensive wheels with high-zoot components.
Most cheaper wheels, like this one, can be brought back to a reasonable level of trueness and made perfectly ridable again.