Having four pairs....and only using each one occasionally.
Actually I have just had a hearing test and my ears de-waxed. The audiologist told me that ear buds, or ear protectors promote wax build-up. I hadn't realised how badly waxed up my left ear was, and once I had the wax removed, I couldn't believe the difference, either IN the audiologist's office, or when I go t home and turned the stereo on. I had to adjust the balance. Unbelievable.