How do you know when it's time to leave your current company and move on?

At the time that you feel frustrated, every thing not showing in dark, there are no sign of an shining bright future!
Then go for a better place

In all honesty, only you can answer this question. That said, of course, I have some suggestions for how you can decide.

Most importantly, if your work is affecting your health, then you need to seriously consider finding a new job. The mental stress from working at a job that you strongly dislike (or with people or a boss you dislike) can have its affects on your health. That's partly why unhappy workers call in sick so often -- it's not just not wanting to go into work as much as you generally are sicker.

If you find yourself living for Fridays and dreading Sunday nights, then that is another sign that it is time to find a new job. While we all love the weekend (and all our days off), we should not be living just for those few days when we are not at work. While our job will always be “work,” it should also be something we enjoy doing. If you dread work, then it's time for a new job.

Another common situation is reaching a plateau at your current job and not seeing any chance of promotion within your current employer. While doing the same job for years is comforting -- because you are an expert at performing it -- it is also a waste of your talents, especially if you have ambitions to do more with your life or in your career. If you want to grow more in your career, then if you are in a job that is going nowhere, it probably is time to seek out a new job.

A situation I am surprisingly finding with baby boomers is finding yourself in a job you no longer really enjoy because you have been promoted out of your original field. Perhaps you were a scientist and loved the aspects of being in the lab but through the years you have been promoted into management and never really get to be in the lab anymore. You do not really hate your job or employer, but you just get very little satisfaction from it anymore. If this is the case for you, it might be time to refocus your career path and find a job that goes back to your career interests.

Finally, of course, if you sense the writing on the wall that management plans to make changes -- that you might be fired or downsized in the near future -- then it is most certainly time to look for a new job. It's much better to be proactive and start your job-search while you have some leverage (and a job) than after you have gotten the pink slip or been downsized.

It is when you are not self-motivated anymore by realizing that your values and career objectives are not tally with what the company offer you. But hold on, try new opportunities within the company first, by transferring around departments, to refresh and learn new things. Different departments may hold different cultural attributes, values, goals that could fit yours while others in the same organization could not. Be a valuable resource that the company MUST retain!

From the beginning, anyone could be a trainee. However, at a certain time, when you accumulate enough knowledge and experience, you will totally become a different person. Then, you will surely find many opportunities for new directions. If you receive a very big job opportunities, you should try after careful excavation. You should know that, the more people you interact with and the more you face the reality of life, the more you can learn from them. No matter how interesting and great you current job is, there are always limitations. Once you find opportunities which are better than your current ones, you should not deny it. Or, you are "stuck" at a work which has an unchanged salary, and your hope about increasing your salary is ... in vain despite your significant improvement. In this case, if you receive an invitation from another company with a job which not only is suitable for your qualifications and experience but also has a better salary, you should consider this one seriously.

Some people start in a company to be happy.

Some start to reach a set goal, usually the top of that company if possible. When you have set your goal and you see you won't be able to achieve it for whatever reasons, your work effectiveness will show. It's time to consider leaving, and perhaps your boss is thinking aIbout that for you already!

Starting with the set goal of getting experience and start your own company or nhay for a better salary is a lie that I deal with from the beginning asking candidate 'what is your dream job/occupation?'.
Unfortunately the answer is often a lie in line with 'I dream of working in insurance consulting for your company!'