The Vanguard S&P 500 ETF (VOO) is generally recommended for long-term investors due to its significantly lower fees compared to the SPDR S&P 500 ETF Trust (SPY), which is more suited for active traders due to its higher trading volume and liquidity. While both ETFs offer similar exposure to the S&P 500, VOO's low expense ratio makes it a better choice for most investors looking to build wealth over time.
For a long-term investor focused on minimizing costs and maximizing growth through compound interest, the Vanguard S&P 500 ETF (VOO) is preferable due to its lower expense ratio of 0.03%, compared to SPDR S&P 500 ETF Trust (SPY) with an expense ratio of 0.0945%. This cost saving can compound significantly over decades, making VOO a more cost-efficient choice for building wealth through passive investing.