What is a Successful Manager?
When can a person reasonably be considered a successful manager?
From the company's point of view, it is a matter of performance management and
KPIs. And there are countless articles on
skills /
traits managers should have.

But when is a person successful as a manager from his/her own, personal perspective? The answer depends perhaps on what is driving that person; what are his/her goals, values, needs, preferences, and identity.
We might use
Maslow's Hierarchy of Needs to illustrate the above.
For example, to some people success can be defined in FINANCIAL terms. A large salary and/or considerable savings provide safety, comfort and status.
For others, their professional achievements or standing/STATUS is most important. Are you a junior, senior, team, general or group manager?
And for others their PERSONAL DEVELOPMENT or self-actualization is what matters most.
While to some, the CONTRIBUTION they make (to their family, organization they work in, country, or humanity in general) is most important.
See also
Drivers and Levers of Employees.
Note that above categories and measures of success are not mutually exclusive and can be combined. Even if in reality they sometimes (seem to) conflict with each other.
⇒ When are YOU successful as a manager? Take some time to think it over. You are the only one who can give the answer.