projective tests:
allows person to "project" personal inner motives onto test
examples: rorschach ink blobs, thematic apperception test(TAT), DAP(draw a person) etc
objective tests:
measurements that are clearly based on the response of an individual to standardized stimuli.
objective testing is bit broader concept that projective, projective test is subjective assessment of personality(measurements that relies on interpretation by an observers judgment) and projective tests isnt the only subjective type of personality assessment.
what works better depends quite alot on what are you trying to gain from assessing the person and what are your skills on interpreting results from projective(or other subjective) assessments.