The Trigger: Disappointing US GuidanceThursday's selloff traces directly back to earnings reports released after Wednesday's close by two major U.S. storage and memory companies, SanDisk and Western Digital. Samsung Electronics, South Korea's largest company and SK Hynix's primary domestic rival, fell alongside SK Hynix, with declines ranging from roughly 5.7% to 6.3% across various points in the session. A Sector Already Prone to Sharp SwingsThursday's decline extended a pattern of extreme volatility that has characterized memory chip stocks throughout 2026. Despite Thursday's steep decline, SK Hynix and its memory sector peers have posted extraordinary gains for the year overall, driven by surging demand for the high-bandwidth memory chips that power artificial intelligence data centers. Analysts Divided on What Comes NextDespite Thursday's sharp selloff, not all analysts have turned bearish on the sector's longer-term prospects.