Fun fact: "Mint" condition coins actually are measured on a 10-point scale (from 60 to 70...because...reasons...as part of a broader 70-point scale also because reasons).
In the video, note how the finished coins are unceremoniously ejected into a big bin straight after striking. During that process, many of the coins get little nicks and bumps and scratches. This has been the way for hundreds of years.
Because of this, most of the mass-production coins out there are far from perfect. So even among a group of coins literally hot off the presses, truly perfect ones (graded 70) are super hard to find. In the world of vintage coins (non-modern era - generally pre-1900), perfect 70s simply don't exist, and 69s go for $hundreds of thousands (or $millions).
This is different for modern coins, particularly for issues where the mints are marketing them specifically for collectors. 70s are easy to find. But for the true workhorse mass-market coins, perfection is not the norm.