According to Compounding Quality (@QCompounding) referencing John Bogle, traders should be prepared for potential 20% losses in the stock market, as market volatility is inherent (source: Compounding Quality, Twitter, June 18, 2025). This reminder is especially relevant for crypto traders, as similar market volatility can be observed in cryptocurrencies like BTC and ETH. Traders are advised to maintain robust risk management strategies to navigate both stock and crypto market swings.