Markets tumbled hard on Thursday with the Nasdaq plunging nearly 2% as the AI stock rally that powered 2025 finally hit the brakes. The biggest loser was Salesforce, the company that makes the customer relationship management software used by businesses worldwide, which dropped 5.3% and dragged the entire Dow Jones Industrial Average down 400 points. This sell off happened even though many AI companies are still reporting great earnings, and it shows you one of the most important lessons in investing: sometimes stocks fall not because the business is bad, but because investors suddenly wake up and realize they paid way too much. Major bank CEOs have been warning for weeks that tech stocks might drop 10 to 20% just to bring prices back to reality after three years of explosive gains. The market also got spooked by weak job data showing October had the worst layoffs since 2009, with the tech sector cutting over 33,000 jobs as companies restructure around AI automation. For student investors, this is your reminder that bull markets don’t last forever, and the best opportunities often come when everyone else is panicking and selling stocks that are suddenly on sale.