They are a complementary team by design, so to speak. The tech guy spots the essence of one's painful problems and elaborates solutions for them. The business guy is doing the marketing and the feasibility analysis.
Then why these two guys so often cannot get along?
Over the years I've seen many different situations: young or even mature people suffering from lack of education and experience, or too much greed. I consider that our personalities are evolving during all our life, and everybody has the capacity to overcome his/her weaknesses, but for turning a project into a success all the team members need to be in their best psychical shape.
Some people are nice one-man business guys - even if apparently they are leading thriving small businesses, all their team members are just executing orders. Other people are bringing the sun with them and turning their competitors in team assets - these special guys sometimes make millions, but most of the time just make happy their families and friends.
About a year ago I had a written job interview, and between others I had to answer this question: "What 2 'unicorn' companies do you consider most over-inflated and subsequently most susceptible to being impacted by a bubble burst?"
My reply stated the following: "...Uber and similar dispatcher companies, picture sharing, text and voice chatting, social networks (SnapChat, Pinterest) might loose even more than 50% of their current market values."
Of course somebody else has taken the job, because the job poster (like many many others) has underestimated the importance of the technological factors in the evolution of business entities.
Those guys bringing the sun with them are natural leaders, they are able to run companies with happy tech guys and business guys, and I'm considering a matter of elementary common sense to vote for them.