Scholarships(just saying) but if u dont get the ATAR then you can do an internal transfer
all a high ATAR does is it makes your life easier in getting into your desired degree
Not wasting parent's money (private school/tutoring) and making them proud
The main one is scholarships which can get you money or extra benefits
Also internal transfer wastes more years of your life which you could spend earning money. Why waste 1 year of studying for HSC then just waste 1+ years later on studying for uni and still running the risk of not having a high enough GPA when you can just work hard for 1 year?