1. Employment opportunities: Jingjing may have found better job opportunities, such as in other jewelry companies or other industries, which can provide better career development and salary.
2. Life changes: Jingjing may need to move to other places for family reasons or personal reasons, so she chose to leave the old jewelry.
3. Career development: Jingjing may have a higher pursuit of her career development. Now the old jewelry can't meet her development needs, so she decided to look for new opportunities.
4. Company changes: There may be some major changes in old jewelry, such as company merger and layoffs. These changes may make Jingjing feel uneasy, so she chose to leave.
The above are just some guesses and assumptions, and the specific reasons may need to be asked by Jingjing herself to get an accurate answer.