The answer to 'why is my deck bare spots' is that there are several common causes, including wear and tear, lack of maintenance, and environmental factors. Bare spots on a deck can be caused by heavy foot traffic, water damage, or pest infestations that kill the wood or underlying vegetation.
If the bare spots are limited in size, you may be able to address them with some DIY repairs. But if the issue is more widespread or the deck is structurally compromised, it's best to call in a professional landscaping or deck repair service to properly assess and fix the problem.