Which SMART attribute trend is commonly used to justify proactive replacement due to wear-out?

• A. TBW trend
• B. Wear_Leveling_Count trend
• C. Power_On_Hours trend
• D. Media_Wearout_Indicator trend

Answer: (D)

The key idea is how SSDs measure remaining life as they wear out from write cycles. The Media Wearout Indicator is a SMART attribute specifically designed to estimate how much life the NAND media has left. As the drive is written to, this indicator changes in a predictable way, usually shown as a decreasing remaining-life percentage. Tracking its trend over time gives a direct, actionable view of wear progression, so you can justify proactive replacement before failures occur.

Other metrics are less direct for wear-out: TBW shows total data written over the drive’s life but doesn’t continuously reflect current health; Wear_Leveling_Count indicates how evenly writes are distributed (which affects endurance) rather than how close the drive is to end-of-life; Power_On_Hours is simply how long the drive has been powered, not how much wear the media has sustained.