This. Assuming your application doesn't have a glaring hole in it that requires explanation, you'll never be faulted for writing a bland personal statement. The radiology residency program director at my medical school once told me that, in ten years, she had only read one "creative" personal statement that was worth anything. She had, however, read many "creative" personal statements that caused her to immediately disregard an applicant.
I empathize with you on this question because I think it's a pretty stupid one. My medical school had a very strong medicine department, so many students ended up in internal medicine. Is that because they were all preordained to be internists? Of course not, and if our school had a decent OB/GYN program then you'd probably see record numbers of OB/GYN applicants.
The truth for many people is that you run across someone, whether it be a resident or an attending, who you think is just great and does a great job of teaching you their specialty. Since we're all pretty cerebral to begin with, that usually sparks enough interest to lead to an application. The "grown-up" word for this is mentorship, and that's something you can talk about in a personal statement or during interviews. It's an angle that's truthful and gives you something legitimate to talk about without coming off sounding like a d**chenozzle.