Is it safe to put all your money in an ETF?

Is it truly advisable to invest all of one's financial resources into a single Exchange-Traded Fund (ETF)? While ETFs offer the convenience of diversification within a single investment vehicle and can potentially track the performance of a broad market index, they do not guarantee absolute safety or protection against market volatility. Are investors fully aware of the risks associated with such a concentrated portfolio strategy? Wouldn't a more balanced approach, incorporating a mix of asset classes and potentially individual stocks or bonds, offer greater resilience and potential for long-term growth? Furthermore, what are the specific risks and fees associated with the chosen ETF, and how do they compare to other investment options? Shouldn't investors carefully consider these factors before committing all their funds to a single ETF?