I would say that the two main dimensions of high performance are Ability and Passion.
However, people are complex and they do not fit neatly into boxes; we often experience varying levels of Talent and Passion from the same person on different tasks in the same project or in different projects.
So what is the most important quality? There is no short answer.
Talent seems an obvious first choice, if we need a complex C# application developing, let’s staff it with the best C# resources we can find. Yet Talent is often over-rated in a team environment. Prima-Dona personalities cause friction as their “my-way, or no-way” attitude stifles collaborative decision making. Likewise, an unwillingness to share information either because it is beneath them or they want to maintain their role as expert (a scarcity model for information) limits trust, saps patience and slows the project. Talent is only valuable if coupled with humility, patience and humour. The days of the invaluable maverick, eccentrics within IT were at best short lived and mostly media generated. Software projects are firmly in the knowledge worker domain. People without the requisite skills for collaboration and communication are of limited, short term value.
What about motivation? Here I am talking about attitude and passion for the cause. The right attitude goes a long way towards fostering collaboration, uniting a team, and building a strong platform for sustained high performance work. Obviously they also need Talent/ to be useful to the project. A well meaning unskilled worker can be found a valuable place on a team, but we need a core set of talent to get the job done, solve the technical problems, and help define the vision and architectural direction.
Given the choice I’d choose Motivation over Talent for the majority of the team as long as we have some talented, motivated people on board. The true importance of Motivation surfaces when we experience the impacts of unmotivated workers or those with a bad attitude. I believe it is more important to act ruthlessly on bad attitude far sooner than poor performance.
The ideas above were taken from a great post, that I trully recomend.