Dear Ritesh,
Navneet's and your doubt is valid. In India, there are mainly three types of employees: Government employees, employees in government-controlled corporate bodies known as Public Sector Undertakings (PSUs), and private sector employees.
The rules and regulations governing the employment of government employees stem from the Constitution of India.
Public sector employees are governed by their own service regulations, which either have statutory force, in the case of statutory corporations, or are based on statutory orders.
Private sector employees, excluding workmen, are governed by respective contracts of employment, and hence Article 16 has no direct applicability.
However, you need to understand that Article 16 has wide implications, and if someone is ready to take up the cudgels, one can pursue this. There are many factors in public employment which serve as a guiding light for private employment, such as DA, Pay Commissions, etc.
The question here is "Denial of equality of opportunity," which assumes that everything else is equal. Assessment always takes place before promotion, real/unreal, and it is independent of the fact whether the whole batch or a single individual is being promoted.
I do not agree that a company will give a promotion simply because of the attrition factor. In private employment, performers are always given all kinds of perks/recognition/rewards, etc., and non-performers are always let go.
However, I agree that the operative word remains "Performance."
Great! Hats off to you for doing that.
Obviously, promotion for a person (Performer) is nothing but a retention exercise. Exit today has undergone a sea change. You want that person to come back and act as the brand ambassador of your company. Promotion during the notice period is the price that you pay for it.
The question here is that your employee has qualified for the performance by putting in hard work and exceeding targets/expectations. You can never become top-heavy by not letting go of your performers.
However, you are correct in saying that some people may use it for personal gains. But, there has to be a system in the company for separating chaff from wheat. Keep the wheat, let go of chaff.
Promotion is always a serious matter. A light matter does not elicit so much response.