Having the same position in the same company for 10 years is not a healthy sign, regardless of what the position is (unless, of course, there's no more people on top of you).
I personally think that you should start searching for another opportunity, an opportunity in which there is a potential for career growth.
Anyway, here are the signs that a project manager should quit his job:
- No growth: The project manager is holding the same position with little or no change in his responsibilities.
- No recognition for his contribution to the company: Project managers, like all other employees, love to be recognized by their superiors, and when this doesn't happen, they will feel that their superiors are either taking them for granted or do not like their work.
- Restricted authority: It is a known fact that project managers do not have any formal authority, but they must be allowed to have an informal one through their leadership and charisma. But if they are blocked to have even this informal authority by the functional managers, then they won't be able to manage any project properly.
- No training: Companies need to train their project managers constantly in order to keep them up to date and keep their skills competitive in this fierce marketplace. If a project manager is not trained, then he will feel that his skills are becoming rotten, and he will start thinking about quitting his job.
- Business model of the company is unsustainable on the long term: Every project manager wants to be safe in his career, so when he feels that at one point the company he's working in will go bankrupt because of a broken business model, he will definitely jump ship.
- Constant conflicts with middle/upper management: People have a lot of issues in their lives, and they don't need more issues/conflicts in their work. So when a project manager starts having daily conflicts that seem to be unresolvable with middle management or upper management, then quitting becomes an option.
- Unresponsive management: A project manager needs a responsive management to get his project done. If the management does not address the project manager's concerns about the project, then the project will be definitely doomed, and the project manager's career will be at risk. The project manager should not continue with the company when he feels that management is uncooperative/not responsive/ignoring his requests.
- No salary hikes: The project manager is either not getting a raise or at best, is getting the 3%-less-than-inflation-rate raise every year.