Why its necessary to give and receive feedback?

It is part of the "2-way communication" needed to establish cooperation, collaboration, corrective actions, adjustments, fine tuning ... etc ..; etc 

to run a routine and daily process smoothly or to face any challenges diligently when it would occur in future with abnormal conditions at compexed business environement

You do not ask this question to an American. It is a way of life. Americans have it all over the three branches of the government. It is called "Checks and Balances".

It is necessary to give and receive Feedback :

*because it encourages your team to continue good behavior.

*Constructive feedback teaches staff about your expectations and coaches them to improve their performance.

*additional way of gaining insights and validate your point of view.

*should a be a learning and growth opportunity  vs. corrective and negative.