Where did you come up with that totally incorrect notion?
Actually, the “S” does NOT stand for Spain, simply because Spain is Espana to anyone who is fluent in the Spanish language. Why would Spanish-speaking people use the Anglicized version of the name of their nation when choosing a title for a car company operating in Espana?
Sociedad Espanola de Automoviles de Turismo originally made Fiats under license. Much more recently, it is a wholly-owned subsidiary of VW. While neither Fiats nor VWs are paragons of reliability, I can’t see how that relates to Spain, as a nation or as a place to manufacture vehicles… or anything else for that matter.
Please explain what this comment of yours actually means…