Paint Correction vs. Wax vs. Sealant
Wax adds shine and a thin layer of protection. A sealant lasts longer and feels slicker. Paint correction is different: it removes swirls and scratches from the paint itself, so it fixes damage, while wax and sealant only protect.
Rule of thumb
If your paint looks dull or swirly in the sun, start with correction (from $500). If the paint looks good and you just want protection, an exterior detail (from $125) will do. If you want long-term protection after correction, add ceramic coating.