A good instrument, left alone, won’t stay good. Whether it’s a piano or a clarinet or a trumpet, the best maintenance work you can do doesn’t involve tuning or oiling or anything mechanical. Those help, but what an instrument needs most is to be played. Good instruments seem to reward regular playing by staying good. It’s kind of remarkable.
Instruments want to be played.
Do you really think your singing voice is any different?
What are you waiting for! Go sing!