If the storage in this Mac needs service
If you receive a notification that the storage in this Mac needs service, it means an error with the Solid State Drive (SSD) has been detected.
The SSD in the Mac includes Self-Monitoring, Analysis, and Reporting Technology (S.M.A.R.T.) hardware. This technology detects blocks of flash memory that have stopped working correctly. The problem can’t be fixed using Disk Utility or any other third-party app.