When you have a musical instrument, you just cannot be careless to let them lie around anywhere. If it is made of wood, a scratch can lessen the value should you decide to sell it. Wind instruments should have proper casing to keep away from dust and insects. A fly that lands on the mouthpiece without you knowing can lead to some health hazard. If you are just resting for awhile, stands are useful like guitar stands and trombone stands. The stand gives a certain limitation for other people to keep away from the instrument especially for children running around.