In addition to what other members have contributed, I wish to share my views.
As you have not mentioned the nature of the job these unskilled workers are performing, I have assumed that they are working as helpers (moving materials, packing, loading, and unloading, etc.). In such cases, there may not be a wider scope for appraising them. As Mr. Bhatia has rightly suggested, you can only go by subjective appraisal, and there may not be any objective appraisal.
Steps to Appraise Unskilled Workers
On the other hand, if these workers are also performing the same tasks as your regular workers, then the scope widens. In such a case, in my opinion, you can follow the steps below:
1. Identify all the skills available in the company and categorize them department-wise.
2. Categorize these department-wise skills in ascending order (from the least skill to the most complicated skill).
3. Prepare a training plan for these unskilled workers in consultation with the respective department heads.
4. Prepare a skill matrix to plot the workers' capabilities for each skill as: a) Don't know, b) Knows but can't do (lacks physical strength, height, can't be spared immediately as skilled in an alternate skill, etc.), c) Knows can do, d) Knows can do and train.
5. Once you have mapped this, you will know the current level of skills of these unskilled workers.
6. Prepare a training card containing the worker's name, identified skill, trainer, job number, quantity produced, quantity accepted, reasons for rejection, and have it signed by the department supervisor and the worker. The card must be filled out every time the worker works in the respective skill.
7. At the end of each training period, conduct an evaluation for each skill acquired by the worker and plot their skill once again in the skill matrix.
8. If you observe a shift in the skill category, you will be able to appraise their performance subjectively, and the process will be transparent. Consider the number of skills acquired/enhancement of skill level over the given period.
9. Skilled workers also earn appreciation in the appraisals based on the number of workers trained by them during a period.
10. Plotting their skills on a radar chart before and after the training period will provide a visual representation of the training acquired.
Objective Rating Method for Staff
For the staff category, in my opinion, you can start with the objective rating method (key performance areas/key result areas/key performance indicators):
a) Set objectives, measurables, units of measurement, frequency of appraisal, and related scores.
b) The total score of the listed objectives should equate to 100 for ease of calculation.
c) The employee should plot their achievements against objectives and score against each objective.
The employee's superior needs to assess and guide the employee to excel in performance. You can also include subjective ratings for the staff category, such as innovation/creativity in work, working coherently with superiors and peers, flexibility in performance, etc. However, each subjective rating must be supported with examples for the appraisal period.
Regards,
M.V. Kannan