Pads that are made of harder materials, such as leather or felt, will typically last longer than those made of softer materials, such as rubber or foam. Additionally, pads that are played in humid climates will need to be replaced more often than those that are played in dry climates.
It is important to have your flute's pads checked regularly by a qualified technician to ensure that they are in good condition. If pads are worn or damaged, they can affect the playability of the flute and can even cause damage to the instrument itself.