Trading various currency pairs will not, per se, ensure diversification. Many forex pairs are influenced by the same macroeconomic drivers. 

During periods of stress, correlations will rise, not fall. This creates concentrated risk disguised as diversification, because real diversification depends on underlying structural differences, not surface variety. Moreover, there is a need to understand correlations and common underlying motivators. 

Hence, diversification is not just risk redistribution; it is risk mitigation. Without proper analysis, diversification becomes an illusion.