What does it take to make it to HYPSM as opposed to the lower top schools? I know all of the top schools are very hard to get in, but what differentiates people who are able to make the extra cut to HYPSM vs those who don’t get into HYPSM but still make it to the rest of the top 10/top 15 schools?
Luck (mostly)
If you aren’t hooked, I’d say EC “pop” is what differentiates the most once you have the stats to show you can succeed academically.
Luck 
Having something they want
“Wow” EC
Understanding that what the college wants is different from the fact you want to attend
Humility, kindness
Not going to name names because it would throw the thread off track, but I think the importance of humility and kindness varies by top school. None of them would reject because of it, but I think a couple aren’t really concerned about that unless you are blatantly awful. Just sayin’.
So if I understand this correctly, they are looking for someone with top grades, stats AND something else that is really good and stands out? Do people with just really good/perfect stats and regular/decent ECs ever get into HYPSM?
Sure. I have heard admissions officers say that they can’t admit a class of all leaders, that they need people who will be club members, too. Also, they are evaluating your accomplishments against your background. Someone who is from a rural area might not have had the same opportunities as someone from an urban area.
Admissions officers always say they are trying to build a “balanced” class. They want athletes, scholars, artists, and doers. They want a cross-section socioeconomically, geographically, culturally. Admissions decisions are also driven by particular needs of the school, such as the orchestra director saying he needs a trumpet player, or by the fact that the school wants someone from North Dakota so they can claim they have members from all 50 states. Unfortunately, you don’t get to see this when you apply. That is partly why I said, somewhat facetiously, that at this level, luck plays a big role.
@intparent I agree humilty seems to be less important in some of these schools. no names…haha
To answer the OPs question, I think the differentiation comes in the form of having tippy top academic profile + something else very memorable, interesting, cool.
Yes. Lots. People said luck but as mentioned it’s luck based on Institutional need which changes from year to year.
I believe the luck component is more than just institutional need. Luck (or perhaps “randomness” is a better word) is involved because admissions decisions are made by human beings, who are evaluating human applicants on subjective, intangible criteria like “EC pop”, “humility”, “kindness”, “memorable”, “interesting” or “cool”. Granted, there are some applicants who have stellar credentials that are readily recognizable by everyone, and they will get accepted everywhere they apply. But for the vast majority of a given class, the decision is not so clear-cut. If I remember correctly, a Stanford admissions officer once said that they could have admitted a second set or even a third set of applicants, and they would have been completely indistinguishable from the admitted class. So, for those cases, “luck” means whether the particular admissions officer assigned to your application liked your application on the day she read it, and saw something in it that made her nominate your application over the other ones she read.
There’s no substantive difference that I can tell being around kids that got into HYPSM and the ones that got in to the next 10. In fact the kids that got into Cal Tech are as good as the ones that got into MIT, ok to be fair, a few of them got into both. As said above, it’s hook and lot of luck, the process is pretty random.
In the workplace there’ no substantive difference at all, I’ve not run into too many YP grads, but again I didn’t see a difference between Stanford, MIT and Berkeley engineering/comp sci grads. In terms of technical ability or leadership or ability to solve problems.
Kids who have accomplished something on a national or world stage. If they haven’t they have to be at least better than their peers from the same high schools. Ivies like musically accomplished kids, it’s a + if you have it, not necessarily a drawback if you don’t. legacy, recruited athletes, URMs and if you’re from North Dakota.
It probably looks obvious inside the admissions offices, but opaque to outsiders.
Consider the following characteristics:
A. High school academic record.
B. Test scores.
C. Extracurricular achievements.
D. Essays.
E. Recommendations and interview evaluations.
F. Institutional needs and wants.
A and B need to be top-end, of course. These are also the most observable aspects to applicants and other outsiders. C and D somewhat observable to applicants and other outsiders, but they may not know how applicants from other high schools compare. E is the least observable characteristic that is directly applicant related. F is obviously difficult for the applicant to observe.
Since how an applicant stacks up to others in C, D, E, F is difficult to observe from outside the admission office, the answer to your question is unlikely to be knowable by outsiders.
The human factor is still important. I believe that the study discussed here
https://www.wired.com/2011/04/judges-mental-fatigue
is relevant. The study found that parole decisions varied greatly, depending on whether the case was reviewed by judges at the beginning of the day, before or after lunch, or at the end of the day. The parole rate was 65% at the beginning of the day, went down to near zero at the end of the morning, and then shot back up to 65% after lunch and then went down again. This is not to say that parole decisions are exactly the same as admissions decisions, but we are still talking about human beings evaluating other human beings subjectively based on written documents. And yes, some applications are indeed clear-cut. But for application decisions that aren’t so clear-cut, you are luckier if your admissions officer reads your file at the beginning of the day than if she reads it at the end of the day.