What is college yield protection?

I've been hearing about the concept of 'yield protection' in college admissions but I'm not exactly sure what it means. Can someone please explain it to me? Is it common for colleges to practice yield protection? Thanks!

Yield protection is an informal practice used by some colleges and universities during the admissions process. The primary goal of yield protection is to maintain a higher yield rate, which is the percentage of admitted students who ultimately enroll at the institution. A higher yield rate is desirable because it signifies that the school is a top choice for many accepted students, and it also helps with rankings and perceived prestige.

Yield protection occurs when a selective college or university either waitlists or rejects a highly-qualified applicant because they believe that the applicant is likely to be accepted to, and ultimately attend, another higher-ranked institution. In other words, the school is trying to protect their yield rate by not admitting applicants who they consider to be a "high risk" of not enrolling, even if those applicants have strong academic and extracurricular profiles.

It's important to note that yield protection is not an officially recognized practice, and many schools deny its existence. It's also hard to determine the exact impact of yield protection on individual applicants, as many factors are considered during the admissions process.

Yield protection is more common at mid-tier colleges and universities that are competing for students with top-tier institutions but is not generally practiced at the most prestigious institutions, such as the Ivy League schools, MIT, and Stanford, since they already have very high yield rates and attract a significant number of highly qualified applicants.

Overall, while the concept of yield protection may seem unfair, it's a result of the competitive nature of college admissions. To hedge your bets, it's wise to apply to a good mix of reach, match, and safety schools so you have options regardless of the outcomes at individual institutions.