How to deal with career failures?

Set realistic goals
Life circumstances are often changeable and unpredictable. To cope with this unpredictability one needs to set a realistic plan. It can be a four-year-plan, having commitment to revise it on an annual basis. A career can fail if a person picks one that he is not fully qualified for. Moreover, some people's careers fail because they made the wrong career choice. Hence, while setting the goals, one must make sure he really wants to do it and that he is completely qualified for it. Update your skills
The failure in your previous attempts will show you the loopholes in your approach and skills. So in your next attempt you should update all your skills that better suite your work and go ahead without getting panic. Updating skills is always a smart move dealing with failures.