What is the main limitation of SMART as described?

• A. It cannot read raw values.
• B. SMART is helpful but not perfect.
• C. It cannot detect reallocated sectors.
• D. SMART warnings always occur.

Answer: (B)

SMART acts as an early-warning system for disk health, collecting drive attributes and flagging anomalies that may indicate wear or impending failure. The main limitation is that these signals are not definitive predictors. A drive can fail with little or no SMART warning, and thresholds and interpretations vary by vendor, so healthy-looking data today can still lead to failure tomorrow. Because of this imperfect predictability, SMART is a helpful monitoring aid but not a guarantee of reliability or timing of failures. It does provide raw attribute values and can report indicators like the reallocated sector count, and warnings do not always occur, which is why the broader, more cautious description—that SMART is helpful but not perfect—best fits.