Spouses who work together double their exposure to harsh and angry words and the damage done can be hard to reverse.

the family unit will be less vulnerable when there is a spouse with a consistent, separate flow of income

We have emotions, preconceived notions and biases, and not all decisions can be made by consensus. 

It is much easier to focus on the role of husband, wife, father, mother if work conversations are kept separate

the family-focused spouse may begin to criticize the business-focused spouse while the business-focused spouse may begin to resent the lack of perceived support for the venture