最重要就這三張圖表，第一張是 2017Q4 資料，第二張是從 2013/04 到 2017/12 的資料，第三張是這三年的資料 (2015/2016/2017)：
唯一有價值的資料是 HGST 的硬碟比 Seagate 好不少，要做出其他結論的樣本數都不夠。
依照往例，Backblaze 每一季結束後不久會放出上一季的硬碟故障率報告：「What Can 49,056 Hard Drives Tell Us? Hard Drive Reliability Stats for Q3 2015」。
如果仔細看的話，小硬碟中 Seagate 的死亡率還是很高 (尤其是 ST1500DL003 與 ST3000DM001 這兩顆驚人的數字)，而大硬碟 (i.e. 4TB 以上) 都還算合理範圍。
值得提的是，其中 HGST 的硬碟死亡率比起其他家低了不少？
文章裡還討論了外接或內接的情況，最後猜測的結論是，Seagate 的這個 3TB 型號的品質特別差，因為 4TB 就正常許多：
While this particular 3TB model had a painfully high rate of failure, subsequent Seagate models such as their 4TB drive, model: ST4000DM000, are performing well with an annualized 2014 failure rate of just 2.6% as of December 31, 2014. These drives come with 3-year warranties and show no signs of hitting the wall.
灰色部份是一月的數據，其他顏色是九月的數據。文中有考慮是否要換成企業級的硬碟 (enterprise drives)，但兩個評估的答案是否定的。
第一個評估是成本考量，就算一般硬碟以三年保固期有 15% 的 failure rate，相較於企業級 0% failure rate 計算 (於是直接算成 10 年)，成本是不划算的：
Today on Amazon, a Seagate 3 TB “enterprise” drive costs $235 versus a Seagate 3 TB “desktop” drive costs $102. Most of the drives we get have a 3-year warranty, making failures a non-issue from a cost perspective for that period. However, even if there were no warranty, a 15% annual failure rate on the consumer “desktop” drive and a 0% failure rate on the “enterprise” drive, the breakeven would be 10 years, which is longer than we expect to even run the drives for.
The assumption that “enterprise” drives would work better than “consumer” drives has not been true in our tests. I analyzed both of these types of drives in our system and found that their failure rates in our environment were very similar — with the “consumer” drives actually being slightly more reliable.