Is design too important to be left in the hands of designers?

Milton Glaser, among other influencial and experienced designers, says it is.
But if we are to agree with this, we must not forget who "leads the boat".

Is Brain Surgery Too Important To Be Left Only To Brain Surgeons?
I think I want my doctor to know what he is doing. His experience and knowledge will let me know he's going to do the right thing. But in the end I have to trust him. Just like a business should trust the designer they hire. I think businesses need to understand themselves and their markets before hiring a designer. Then they would know their own problems. Designers could then always give promising results. Design is also a very broad usage. There is aesthetics and functionality, and can be implemented in a diversity of ways across all forms of design.
Edgar Zorrilla, who commented this.
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(Open for further comments, as are all posts)