Olive Oil Is Not All Created Equal
Most home cooks use one bottle of olive oil for everything, which means they are either overpaying for finishing oil or wasting good oil in a hot pan. The fix is to keep two bottles on the counter: a workhorse and a finisher.
Workhorse oils are usually labeled extra virgin without an estate or harvest date. Use them for sauteeing, roasting, and shallow frying up to about 375F. Look for tinted glass that protects the oil from light, and do not agonize over the price.
Finishing oils are pricier, single-estate, and often stamped with a harvest year. Save them for salads, a drizzle over grilled fish, or a final flourish on a steak. Their grassy, peppery character would be wasted in the heat of a pan.