1. Foot bath shops have no registered or updated information: some foot bath shops may not have registered or updated information on the navigation software, which makes it impossible to find them on the navigation software.

2. Incomplete or inaccurate data of navigation software: The data of some navigation software may be incomplete or inaccurate, which makes it impossible to find some foot bath shops.

3. The location of foot bath shops is unclear or difficult to find: Some foot bath shops may be located in relatively hidden places, or the location is unclear, which is difficult to find on navigation software.