Recently, AI-related companies experienced a substantial decline in stock market value, collectively losing $190 billion. This downturn occurred after Microsoft, Alphabet, and Advanced Micro Devices reported their quarterly results, which failed to meet the high investor expectations set by the previous AI-fueled stock market rally. Alphabet's shares dropped significantly due to its ad revenue falling short of expectations and its announcement of increased spending on data centers for AI development, highlighting the cost of competition against Microsoft. Microsoft's stock also saw a decline despite beating revenue estimates, attributed to new AI features in its cloud and Windows services. The overall market reaction reflects the volatility and high expectations surrounding AI companies in the current economic climate.