Think of the template as the fin’s outline. A bigger, wider base equals more drive and stability—perfect for powerful turns. A more vertical, swept-back fin offers looser, pivoty turns for quick snaps. If you’re a powerful surfer on a shortboard, you might want a template with lots of hold. For a fish or a groveler, a smaller, more flexible fin helps with quick releases in weaker surf. It’s about matching the fin’s personality to your wave and approach.