SeaTools has vendor-specific abilities, but does not give detailed information. If you want more detailed information about what is going on in the drive, you should try using smartmontools, or some other SMART disk software. My guess is that the main display only shows SMART tripped for serious errors, and that running the test gives indications of less critical SMART events, like a reallocated sector. If you use smartmontools, look for the attributes "Reallocated_Sector_Ct" and "Offline_Uncorrectable" to see if any sectors have gone bad. It is not uncommon to lose one or two sectors during the life of a drive.