Its may vary as there can be various reasons that the poor performance can be attributed to.
For example; it usually happens that students after burning their candle from both the ends in their 10th take a little easy in their 11th. TO add on , is the newness of college life, new friends,college,crowd etc. So, in this case initial phase of 11th is spent in adapting to all these changes. And thats how studies get affected. Nevertheless, the students do pick up pace after this, and compensate for the lost studies in the later half. And this is quiet normal.
On other hand there are cases where the students due to lack of awareness about the careers, curriculum and about themselves make an incorrect decision on choosing their stream. In that case it becomes necessary that you understand and jot down your career goals. In case of any difficulty to do that (which many students face) seek professional help in making an appropriate career decision.
For more information on how the career tests help log on to http://www.youngbuzz.com/career-assessment/role-assessment-career-counselling
Also check out the sample report of how your career report will look like.
Hope this answers your question.
Kindly revert for further queries.