Partnerships are marriages. After the love affair and the lust wears off, they must survive on character, synergy, and complementary attributes.
My early entrepreneurial ventures were all partnerships, and all miserable failures. Not that my partners were bad people, but our work ethics, values, and visions were not compatible. I remember one partner had a normal 9-5 job and was active in intramural sports; the business was number four or five on his priority list. The other partner was out working four businesses, including ours. That left my business and me, which was priority numero uno. Do you see an issue here?