The personal statement is also a great place to explain more serious problems, like less_than_ideal grades or test scores. Don't be afraid to write something like, "I don't test well" in the statement. As long as you can provide a good reason for you app's problems, it's okay to address them directly. You won't be able to hide it from admissions officers anyway, so providing a reason for problems is always preferable to ignoring them.
Take a minute and think about what most students are electing to write about in a medical school personal statement. 5ꯠ times, a medical school admissions committee member sees: "I want to be a doctor," "I want to help people," "I have wanted to be a doctor for a long time." To an experienced admissions committee member, these cliched reasons say, "I know I want to be a doctor but I don't really know how to express why I want to do it. I don't have specifics, clear motivation. I don't have a specific orientation. I just want to do it." To write a medical school essay that's great, you've got to transcend generalities like that in order to be persuasive. Because if you don't, what's going to happen is your reader is going to say, "I've read this medical school personal essay a million times before."And although it's a nice medical personal statement, it has nothing new, nothing unique to you. It causes your reader, the person who's going to determine whether or not you get an interview, to look at other aspects of your application to try and get some sense as to who you are. And that is going to be experiences, it's going to be grades, it's going to be MCAT score. Your reader, the committee member, is really going to be stuck, struggling to figure out why you're applying.