We do need objectivity.... 

Study critiques schools over subjective grading
http://articles.latimes.com/2009/oct/04/nation/na-grading-policy4

Google's Other Big Research Project: Curbing Its Own Prejudice
Even for a company that's trying to produce driverless cars and "solve" mortality, getting employees to overcome their own biases is a challenge.
http://www.theatlantic.com/business/archive/2015/04/googles-other-moonshot/390558/

"The human understanding is like a false mirror, which, receiving rays irregularly, distorts and discolors the nature of things by mingling its own nature with it."
- Francis Bacon