Why do pianos go out of tune?

There are a number of factors that contribute to your piano going out of tune, probably the largest factor are changes in humidity and temperature. Many parts of the piano are made of wood and expands and contracts during changes in humidity and temperature. Also, normal playing of the piano causes it to go out of tune. During the dry months in the winter, your piano will want to fall flat. During the wetter, more humid months you piano will want to go sharp. But I hardly play my piano, should I still have it tuned?Yes! Your piano strings are under a great deal of tension. After years of neglect the pitch your piano will have dropped, sometimes very drastically. Not properly maintaining your piano could result in possible string breakage. As we always tell our customers, tuning your piano is like changing the oil in your car, do it faithfully and regularly. You wouldn't wait until you hear metal grinding to change your oil would you?