1. I believe that changing jobs in your 1st 3 years of your career is good for your career.
- New projects / work
- Chance of learning more
- Chance of working with big companies
- Better Salary (Its important.. but not always..)
2. After working for 3 yrs till now you come to know which domain/field you want to take your career, for example I thought of moving from software developer field to Marketing/Sales well its all depends on your strengths and interest in field you want to be.
3. And now after working for 6 or more years, now you should try to look into more challenging job and start looking yourself at middle level management along with good package.
4. Now once you have experience of 9+ years of experience you should try to move from job when you get top management level offer where you can add value to organization from your past experiences.