The reasons for this are clear:
- Academic readiness. You are at your peak in terms of academic performance when you are fresh out of school. You have honed your study habits and you are accustomed to taking law school exams.
- Retention of substantive law. Your memory of your law school subjects is freshest right out of school. You will certainly forget most of the substantive law that you learned over time. Therefore, the longer you wait after graduation to sit for the bar, the more information you will need to re-learn.
Do not think that if you put off the bar exam to give yourself more time to study, that you will have any advantage over those who jump right in to bar review after graduation. I have heard this rationale before. It strikes me as nothing more than procrastination.
If you must postpone for financial, medical, or other unavoidable reasons, that is one thing. You should not try to study for the bar exam when you are under stress or unable to give it your all.
However, if there is nothing holding you back from taking the bar exam after graduation from law school, then do not look for excuses to put it off. If you think you need extra time to prepare, then look into getting your bar review materials early and begin your preliminary bar prep during your final semester of law school.