Hi Harsh,
A private employer CAN reduce an employee's salary if the employee fails to meet the performance standards of the employer. (it can apply to other T&C of the employer too)
However, this is a very very stringent action which is used as a last step as this is highly demotivating.
Your friend cant sue the ex-employer nor get any money from them. If your friend really wants to improve, then he should find out from the employer why exactly his salary was reduced and how he can improve his performance (if that was the reason).
A private employer CAN reduce an employee's salary if the employee fails to meet the performance standards of the employer. (it can apply to other T&C of the employer too)
However, this is a very very stringent action which is used as a last step as this is highly demotivating.
Your friend cant sue the ex-employer nor get any money from them. If your friend really wants to improve, then he should find out from the employer why exactly his salary was reduced and how he can improve his performance (if that was the reason).