What the driver knows
The car pulls, the steering wheel is not straight, the steering is restless, or the tires only slide on one edge. A pothole or chassis repair can throw off the geometry.
First the chassis, then the measurements
Adjustment is pointless if there is play in the axle or incorrect pressure. That's why we first check the joints, arms and tires.
What you get by tuning
Correct values improve stability, steering precision and use of the entire tire area. After work you will get output values.
Every vehicle and fault is different. This article provides general guidance; an inspection of the specific vehicle determines the correct procedure.