Why was the Greek column invented?

I have found that the Corinthian Order of column has on it the Acanthus leaf. This is one of the oldest Mediterranean flowers and represents long, enduring life.

Also, in Christianity, the thorny leaf of the Acanthus flower was known to represent pain, sin, and punishment (due to Christianity trying to get attention away from the looking toward several gods).

In Mediterranean countries, it represents immortality

(sorry for the spelling errors)