If you have been recently consistently applying for the new job openings in your professional field and failing somewhere along the recruitment process, there could be a number of possible reasons for this.
1. Your resume could be failing you. If you are truly qualified for the jobs you have been applying for, yet you are not even getting called for the initial job interview, then it could be your resume that is failing you. At the initial recruitment stages, employers have very few ways of short-listing candidates. And given two candidates with the same qualifications, rather than toss a coin to decide who to shortlist and who not to call, an employer will typically look at their resume and how it presented to make that decision.
2. Your skill-set could be failing you. If you are getting into the initial short lists, and then failing in the aptitude tests somewhere along the way, it could be that you need to work on your skill-set. You could take some courses or do some serious professional reading to update yourself on the developments in your field.
3. Your interview skills could be failing you. If you are getting the initial interviews, passing the aptitude tests and still missing out on the job, then it could be your interview skills that are failing you. Employers use interviews to gauge your interpersonal skills, your communication skills and possibly your integrity. And however good your qualifications might otherwise be, if you fail in these areas (which is gauged through the interview), then the employers might have a problem taking you on. To mitigate this problem you might consider taking time read on proper interview etiquette and may consider engaging the services of an experienced human resource consultant to coach you on how to ace your interviews.