It means the drive was unable to calibrate itsself first try, aligning the heads and tracks on powerup. It is possible your drive is beginning to fail and it would be wise to back up it's contents now. SMART parameters do not always accurately predict drive failures (see google study) but you do need to keep an eye on that drive for additional problems, or remove it from service. Another program helpful with the health of a HDD is HDSentinel.