There's a rhetorical technique called "dubitatio" - where you deliberately act unsure, less skilled or less intelligent in order to make yourself sound more credible. E.g. "Although I'm just a simple man unused to public speaking I think...." Obviously it depends on the audience you're appealing to, it works best with people who mistrust skilled orators

(George W Bush did this a lot, his famous 'Bushisms' were almost all deliberate, and playe to a base who distrusted 'elites' and made him sound more honest and down to earth.)