Do you make workers evaluate their supervisors and why?

Individual feedback is encouraged from the team members on their immediate supervisors, this helps in having a fair idea about the semntiments within the team concerning their immediate as well as higher managers.  It also helps sort out differences which may sometimes arise due to improper communication, grapewine and passing down of information.  Such feedback also helps in understanding and developing from a managerial aspect as well which also includes self development as a manager.  Most importantly, such discussions help win the confidence of the team and majorly contribute to the aspect of team spirit. 

They can complain, but it does not go vice versa in evaluation.

When it's over

No because sometimes some workers are not fair about their supervisors and this will effect on the evaluation.