Part of the issue with MCAT retakes is that students take an April or May test, submit applications without knowing their MCAT score, now feel pressured to either change summer plans or squeeze in MCAT studying to take an August exam. So again you don't know the score and you are late in the cycle. And now you have taken it twice. Third time is really the useful limit
I am a very big believer in not applying until you have your MCAT score and therefore a big believer in taking MCATs early. Additionally, I am not a big believer in late August MCATs as retakes as your chances are reduced simply because of the rolling admissions process.
The question I always ask students is your goal to get into medical school or to get into medical school quickly?
If you do poorly an an MCAT you need to find out why, prep again, take it again only when ready and then only reapply when you know the score.