I was thinking the first gelatin finger he made was just a smooth finger-shaped mold and inferred that it worked by simply pressing the pattern left by the oil

I was thinking the first gelatin finger he made was just a smooth finger-shaped mold and inferred that it worked by simply pressing the pattern left by the oil residue of the last person to place their finger on the pad. I thought that was pretty cool, but then wondered why they considered the second more arduous process of printing and etching a fingerprint with the same success rate more interesting. I was thinking, well that can be solved simply with software. Like don't let the same person enter a door twice in a certain time-window. Then I realized the first method meant you actually had to mold a finger that already has access, fingerprint and all. Oh, ok now the second more arduous method is more impressive.