Should couples keep separate bank accounts instead of merging everything?

This argument probably falls into similar territory as arguments for or against prenuptial agreements. Bank accounts can be kept separate for those who have reason to doubt the relationship will always be secure. However, the act of having separate bank accounts, similar to establishing prenuptial agreements, indicates that there is an element of distrust in the relationship which is something that could spread like a cancer. Eventually, this could be a self-fulfilling prophecy where the perceived distrust and secrecy can erode the foundation of the relationship, leading to separation and self-confirmation that it was correct to keep finances separate.