Cursi

Why is Lola Flores cursi and other versions of Lorca not cursi?  Why is declamation more so than singing, most of the time (mutatis mutandis)?

It seems paradoxical that spoken word should be so prone to this treatment while musical versions are not. Declamation only moves in one direction (toward cursilería) or remains dry and dispassionate, but vocal music has an infinite variation in tone and emotion. Is it because actors are so bad?  (But poets themselves can we bad too).