What will happen if investors are concerned about the valuation of risky assets?

Monetary policies in OECD countries will remain expansionary, which will continue to increase the liquidity available for investment. Initially, this situation led to a sharp rise in share prices and corporate valuations. But what if investors start to be concerned about the high valuation of risky assets? The only solution is for them to return to risk-free bonds, which would lead to a further fall in long-term interest rates, despite the economic recovery.