This is one of the most frequently asked questions to me in every forum and in every information session when I was the Director of Admissions at ISB. Here are some of the key takeaways for you (this applies to all schools):
1. There is no benefit to applying in earlier rounds, which means your application would not be given any additional points
2. You do get benefits in scholarship with some schools as they clearly spell out that in order to be eligible for scholarships, you should apply in so and so rounds only.
3. Apply only and ONLY when you feel your application is done properly, meaning essays and interview preparations.
4. A school would not admit a less deserving applicant just because the person has applied in earlier rounds.
5. The conception that in the first round all seats are up for grabs is wrong. If you are a borderline case, at max you would be on the waitlist, and that may or may not get converted.
6. One key benefit of earlier rounds is that you get plenty of time to prepare for the course, relieving you from office, etc.
7. If you are applying for later rounds, be preapred to join at a much shorter notice.
To sum up, you do not get benefit as far as evaluation matrics are concerned. The benefits are largely administrative for you.
Hope this helps to some of you.
Thanks,
Manish (Founder - TutelageX.com)