That is because more selective colleges are already choosing kids who will likely succeed in life. Most high stats kids are smart, driven, ambitious, more likely to be middle class and higher by SES, and they usually have a clear plan for the rest of their lives. So most selective colleges help kids on their way, but rarely “turn them around”.
To “change lives” in the sense of the list, a college needs to be the type that will help kids who are less ambitious, less driven, often lower SES (though rarely very low SES), get their act together, plan for the future, and find a place for themselves.
Kids who are accepted to WIlliams, Carleton, or Pomona would generally be fairly successful places even if they didn’t attend that college. This is less true of the kids who attend the colleges on the CTCL list.
Now, there are also a large number of public universities which also change lives, likely even more drastically. However, these universities also generally have higher attrition rates. So UIC has probably changed more lives that most colleges. However, 40% of the kids who attend do not graduate. I would guess that Community Colleges are the colleges which have the most profound impact on the lives of their students.
I would also like to point out that 9 of the colleges on the CTCL list are Posse partners, some of the colleges that we’ve “added” are also Posse partners - Hobart and Smith, Depauw, and Union.
Interestingly, Grinnell, which was on the list, but was removed when it became more selective, also ended up terminating its partnership with the Posse Foundation when it became even more selective.