Why Design-Build Contracts Exist and their purpose.....

Design-build is a contracting method widely used around the world. This contract combines design and construction, often called project delivery, under a single agreement. 

The Design-Build approach is simple. There is no 'I' in a team. The Design-Build approach is not meant to be just for one person. It is a group of teammates participating in achieving the same goal. It doesn't matter how great a superstar you are, you cannot win the championship game without your teammates.