Most colleges that require a letter of recommendation also ask you to fill out a form that the writer sends to the college along with the letter. One of the questions on that form asks you if you agree to waive your right to access the letter in the future. If you waive your right, it means once the writer sends the letter to the school, you have no right to view it. You will never know what the writer said about you or whether it helped or hurt your chances of admission. I know–that sounds risky.
Still, you should always waive your rights to access.
Here's what happens when you don't waive the right.
1. You're essentially telling the writer that you don't trust him or her to do a good job. And you're making that implication while asking this person to do you a favor. A teacher or counselor can't help but be a little offended by that. And offending the person you want to recommend you is never a good strategy.
2. A writer who's worried that you'll see the letter one day is often less likely to be honest, and more likely to say things that are technically positive but widely recognized by admissions officers as generic statements that mean nothing. That's bad for you. It's the difference between…
"William is never going to be a chemist. That much is clear. But while he's struggled at times in my class, he's cheerful, he keeps trying his best, and he's never given up on chemistry. I like that in a student."
"William has shown consistent effort and is both diligent and determined."
That second example means absolutely nothing to an admissions officer. You are far better served by an honest and revealing recommendation, even one that acknowledges a weakness, than you are by generic faint praise.
3. The college will wonder why you didn't feel comfortable enough to waive the right, and what you were worried the writer might say about you.
If you're feeling uneasy about waiving your rights, consider asking someone else to write the letter, someone who's more unwaveringly positive about you. And if you're still uneasy, try to relax. Teachers and counselors are out to help, not hurt, students. Just about all of them will do their best to say something positive about a nice kid.