Why does a lack of diversity of consciousness costly to individual and organizations. Are there any examples?

Answer 1

Diversity of consciousness, or thought, creates forward thinking and constructive change.

Lack of diversity creates stagnation of the mind and consciousness as well as the physical in the form of the genetic pool.

An example would be the rigidity of thought, behavior and lack of imagination evidenced by what we know of the Neanderthals. As a result, the species ceased to evolve and paid the price of extinction.

Answer 2

Diversity Consciousness

Answer 3

I looked for an exact meaning to "diversity of consciousness". Closest thing I came to was this entry found in the Forward of the book "Diversity Consciousness" by Barry F. Kavanagh and Patricia L. Bucher:
"Not long ago, I happened to pick up a magazine that featured this advertisement: "Life without technology isn't an option." As we begin the twenty-first century, it is becoming increasingly apparent that life without diversity is not an option either. Our personal worlds are expanding as people and cultures throughout the world become more and more interconnected. Human diversity, in its many shapes, forms, and colors, is an integral part of our everyday life. As a result, each of us desperately needs to develop our 'diversity consciousness': our awareness, understanding, and skills in the area of diversity. "1

I guess a quick and easy answer to not being diversified, culturally, is the loss of different view points and experiences.
To put it in a very simple example, say you came from an island that only ate apple pie, because the island only had apple trees (of course the island is fictional). If you keep rejecting "them" (anybody outside your comfort zone - in this case anyone who challenges that apple pie is the only pie there is) then you never get to find out about cherry, coconut, and blueberry pies.

Culturally you are missing out on what other cultures and people have experience with.

You can probably get a better answer if you read the book I quoted from.