The present study discusses the nature and development of a Tungusic phoneme*K- that has proven difficult to reconstruct. It is only fully preserved in one subbranch of the Tungusic language family and today is usually considered a velarfricative *x- (Benzing 1956). However, there is evidence from a Tungusic languagecalled Alchuka hitherto almost unknown outside China (Mu Yejun 1985, 1986, 1987,1988). In this language the phoneme is, somewhat irregularly, preserved as unaspi-rated k-, which may corroborate its reconstruction as a plosive (Rozycki 1993). Themain focus of the paper is the role of the phoneme in the interrogative system ofProto-Tungusic as well as the detrimental implications of its loss in most Tungu-sic languages. In Proto-Tungusic the phoneme had the function of a submorphemeor resonance similar to English (Bickel & Nichols 2007, Mackenzie 2009).Its loss led to incoherent interrogative systems with a large number of individualforms that are synchronically opaque, i.e. to complexification. Finally, the questionis addressed whether this can be considered a “change for the worse”, as indicatedby the title of this volume.