Honor the commitments you have made to others. When it comes to your career you are as good as your reputation and your credibility. Always play the long game and look at least 3-5 years ahead (go further out if you can as well) and keep your goals in mind as you make decisions.
Show determination, commitment and endurance when it comes to projects, operations and even your entire employment history. Invest time, energy and effort into everything you do and move onto new opportunities only AFTER your current place is in a much better place then it was when you found it.