Tim Harford's Cautionary Tales Dec 20, 2019 podcast episode tells the tale of Keith Jarrett's Köln concert , a compelling story of rigid requirements that came up against a limited situation. Jarrett, who is extremely particular about his equipment and venues, was booked to play the Köln opera house and almost refused to play due to the poor state of the instrument, reportedly a practice piano with a tinny sound, unavailable high and low registers, and inoperable pedals. However, he did play and played to a sold out house, and the recording of the concert led to one of best-selling jazz albums ever.