Beethoven’s Piano Concerto No. 4—which, in 2021, was the second-most performed piano concerto at Carnegie Hall (with 192 performances)—had an inauspicious beginning.  Its first private performance was in March of 1807 by Beethoven at the home of one of his patrons, Prince Franz Joseph von Labkowitz, an aristocrat of Bohemia.  It premiered publicly—again with Beethoven playing—on December 22, 1808, as part of a four-hour-long program that included premiers of his Fifth and Sixth Symphonies during a cold snap at Vienna’s unheated Theater an der Wien.  That caused one commentator to remark that the marathon program was “too much of a good thing” but another to claim that the Fourth was “the most admirable, singular, artistic and complex Beethoven concerto ever.”  The program included Beethoven’s Choral Fantasy, which fell apart during the performance and had to be restarted.