In art as in lovemaking, heartfelt ineptitude has its appeal and so does heartless skill, but what you want is passionate virtuosity.

John Barth (b. 1930) American writer
Quoted in Charles B. Harris, Passionate Virtuosity: The Fiction of John Barth (1983)
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Quoted as such in the introductory materials, without specific citation. Barth used the phrase on multiple occasions, including:

• "My feeling about technique in art is that it has about the same value as technique in love-making. That is to say, on the one hand, heartfelt ineptitude has its appeal and, on the other hand, so does heartless skill; but what you want is passionate virtuosity." [first used, in Alan Prince, "An Interview with John Barth," Prism (Spring 1968)]
• "Heartfelt ineptitude has its appeal, Dunyazade; so does heartless skill. But what you want is passionate virtuosity." [Barth, Chimera (1972)]