Genizot, storage rooms for holy books and objects (lignoz, in Hebrew, means to hide or put away, are particularly busy in the days before Pesach, when people want to clear out their homes.
The Sages thought it inconceivable that we would simply throw away a holy book or object when it no longer filled its purpose.
The Talmud says that holy books cannot be destroyed if they wear out but should be buried in a cemetery, ideally alongside a Torah scholar (Megillah 26b). Accessories such as a tallit bag or a box for an etrog also require some kind of storage, but not in a cemetery.
These days, when so much is disposable, we do not think of our acquisitions as with us for life. The laws of geniza are a corrective to this perspective and remind us that holy possessions should be treasured.