Ppraaisal System The Case of Kuwait Oil Company

The main question:
How does the appraisal system contributes to enhance employees performance? The case of Kuwait oil Company.

Notes:
I will attach some documents. Also you can use the website for Kuwait Oil Company (KOC):
I will attach it also.
Organization chart will be attached:
Chairman and Managing Director(C&MD)-->Deputy Managing Director(DMD)(about 7)-->Managers(about 40)-->Team Leaders(about 200)-->Seniors-->Engineers and so on...
Research guidelines structure and guidelines will be attached.
Appraisal forms and others will be attached.
SOP (Standard Of Performance) forms divided to four types:
. Special Contracts.
. Circular appointed employees (team leader and above).
. Non-circular appointed employees (Non management employees like seniors and specialists).
. Non-circular appointed employees (Grade 15 and below).
In case if any information missing, tell me to provide it.