Should I submit a personal statement even if the program doesn't require one? One of the programs I'm applying to doesn't even mention a personal statement, but I have one written for other programs that do require it. Should I submit it anyway under the document upload section, or just leave it out?
You can certainly ask the program if they'd be OK with you sending a statement of purpose (or anything else they didn’t ask for) in addition to the rest of the application. If so, then go ahead. But in general, you shouldn't provide information that isn't requested for by the program in question. Information not asked might may not be considered, and may hurt your application.