But temperament, intellectual capabilities and many other traits do.
Some individuals are couples unto themselves, fusing contrasting and complementary traits.
In my experience, your intellectual capability and skills will take you only so far.
Institutionalisation creates an increased likelihood of reactive attachment disorders, behavioural issues, reduced intellectual capability and poor physical health.
"The way I've overcome that has been to show my intellectual capability and, more importantly, how I can apply my intellectual capability to critical problem solving," she told me.
"Ninety percent of what lawyers do today cannot be automated," said Levy, because it requires intellectual capabilities and decision-making that exceeds the capabilities of today's technology.
More than 85% believed that having gone through the Ph.D. improved their social and intellectual capabilities and enhanced their quality of life.
If the choice is strategic, they will work to build their capabilities and complementary capabilities together over time.
Scientific detachment and caution under dictatorship can be complementary traits, and in Merkel's case they were joined by the reticence, tinged with irony, of a woman navigating a man's world.
It became obvious to us that the great marriages have the longest list of complementary traits.
Gerald Corbett, chairman of Betfair, added the deal makes "huge strategic sense by bringing together two industry leading and successful businesses and providing enlarged scale, capability and distinctive, complementary brands".
