In a study of politeness published in Verbum et Lingua, a journal of the University of Guadalajara, Mexican speakers were asked what courtesy is. One answered: “La cortesía y la educación. De hecho, en algún punto hasta pueden considerarse sinónimos” (Courtesy and upbringing. In fact, at some point they can even be considered synonyms).
Another said that courtesy was “no precisamente para caer bien, sino por el hecho de tener educación” (not exactly to be liked, but because one has been brought up well).