Yahoo Finance analysis suggests that Amazon and Microsoft are tech stocks worth increasing holdings in, while Tesla should be avoided for now. The analysis believes that Amazon and Microsoft have diversified businesses, with strong core operations (e-commerce and software) and high-growth cloud businesses (AWS and Azure). As of the end of the first quarter, AWS and Azure were the two largest cloud platforms globally, with market shares of 28% and 21% respectively. AWS accounts for 61% of Amazon's operating income, while Microsoft's Intelligent Cloud division achieved $100 billion in revenue for the first time in the latest fiscal year. In contrast, Tesla's stock price has fallen by over 16% this year (as of August 21), making it the worst performer among the "Magnificent Seven." Its valuation is excessively high (forward 12-month P/E ratio over 205x), its core business (car sales) is stagnant, and it is burning cash on long-term projects such as robotaxis and humanoid robots.