The tech giants that contributed more than half of the S & P 500's 23 per cent gain last year may struggle to dominate the market in 2025 as profit growth slows. The profit slowdown "may surprise some hardcore investors who are betting on these very high double-digit growth rates," Lisa Shalett, chief investment officer at Morgan Stanley Wealth Management, said on Thursday. "The idea that they as a group can trade together and lead the market may falter in 2025."