Samsung is implementing a major user policy change after four years of Samsung Health (which used to be S Health back in the day. What's changing? Great question. The service is about to make Samsung Accounts mandatory for all users of the service. This is due to the fact that before, you didn't need an account to access the mobile and wearable app.
When you first set up the services, you were presented the option to make a Samsung account. However, all you needed to do was simply press 'Skip' and that was the end of it.
This change will come with Samsung Health version 6.15. Which should come to our devices on January 21st according to the latest Samsung Health change-log.
Users that do not have an account may find themselves not that bothered as you get an extra feature with meaning an account. This is where you can back up your Samsung Health data and sync it across your devices. Who doesn't love consistency?