For decades, promotion was considered the ultimate prize of professional life: higher pay, greater prestige, more influence. Reality, however, shows that “moving up” the career ladder is often a far more complex matter. Behind this hierarchical “climb” lies a phenomenon that has occupied economists, sociologists, and human resources executives for years: the so-called Peter Principle.

According to the Peter Principle, people are promoted because they are good at the job they do—not because they are suitable for the job they will do next.

The theory was formulated in 1969 by Canadian educator and author Laurence J. Peter, who wondered in a 1974 BBC interview: “At what level of our incompetence do we find ourselves as employees?” More specifically, he argued that in a professional, hierarchically structured organization, every employee tends to be promoted to the level at which they cease to be effective. Put simply: people are promoted because they are good at the job they do—not because they are suitable for the job they will do next. Despite its satirical tone, the theory has proven remarkably resilient over time.

When success becomes a trap

The problem begins with a seemingly logical practice. An employee performs exceptionally well in their role, stands out for their skills, diligence, or results, and as a reward is promoted. However, the new position often requires a completely different set of skills. For example, an excellent salesperson may become an average—or even poor—sales manager. A gifted engineer may struggle enormously as a team manager, since technical competence does not automatically imply managerial ability, emotional intelligence, or strategic thinking. Yet organizations continue to operate under the assumption that success in the present guarantees success in the future.

The result? People trapped in roles where they underperform, feel insecure, stressed, and professionally burned out—and organizations filled with managers who are neither happy nor effective.

The drop in performance after promotion

Research in recent years has begun to empirically confirm what the Peter Principle has argued for decades. Studies in large companies show that, in many cases, employee performance declines significantly after promotion—especially when individuals move from technical to managerial roles. The explanation is simple: the indicators of success change. Where individual productivity once mattered, people management now takes precedence. Where knowledge and experience once sufficed, communication, leadership, conflict resolution, and difficult decision-making are now required. Many people have not been trained—and may not even wish—to operate in this way.

At the same time, a psychological burden is created: promotion is seen as a “one-way street,” while returning to a previous role is viewed as failure or demotion, even when it would be a healthier and more productive solution.

Why do companies persist?

Despite the obvious pitfalls, businesses continue to rely almost exclusively on promotions as a reward mechanism. The reason is both cultural and structural: in many companies, vertical advancement is the only way to increase an employee’s salary or status. Horizontal development—deepening expertise in a role without managerial responsibilities—is rarely recognized in the same way. As a result, employees are pushed to seek promotions even when they do not match their skills or desires. Moreover, evaluation processes often measure “what someone has done” rather than “what they are capable of doing.”

The consequences are not limited to the individual. The Peter Principle has a real economic cost. Poor managers lead to low morale, higher staff turnover, and reduced productivity. Entire teams can become “blocked” because someone assumed a position of responsibility without the necessary tools. In the long term, a culture of mediocrity emerges: the most capable are promoted until they cease to be capable, while those truly suited for leadership roles may be left behind because they did not stand out technically.

Is there a way to break the vicious cycle?

Some companies are trying to rethink how they view career progression. They create “career ladders” that allow employees to advance financially and institutionally without taking on people management. Others invest seriously in training before—not after—promotion, preparing employees for their new role. A crucial step is also a change in mindset: accepting that a promotion is not always a sign of success, and that stepping back or changing roles does not equal failure. On the contrary, it can be a sign of maturity, both individual and collective.

So what does this mean for employees? For those facing the prospect of a promotion, the Peter Principle serves as a warning. Before saying “yes,” it is worth asking: Do I really want the new role, or am I simply afraid to say no? Do I have—or can I acquire—the skills it requires? And, most importantly, what truly makes me professionally fulfilled?