Answer: Authenticity
Step-by-step explanation:
Authenticity refers to the genuiness of a product, having the qualities it claimed to possess. Mateo is concerned about authentic 1920s watches and not any watches produce in 1920s.
He is not interested in the periodicity since he his not interested in the watches reoccurrence in the years, reliability is the quality of been dependable and he knows not all are dependable since some has been adjudged as fake,
Furthermore his not interested in their importance which refers to the cannonicity nor the stability for a product can be stable but not good enough.