Pretty sure it's an American thing, the idea that you need several checkups a year as if you were a car that constantly needs maintenance, and we can debate forever why that is (my bet is money). It doesn't seem to happen in countries with socialized healthcare where care is distributed accordning to criticality and population risk rather than what generates the most revenue. If you're in your 20's or 30's the odds of you being affected by something are miniscule. It doesn't hurt to get a checkup every few years I guess, but several times a year is ridiculous.