Just as importantly, the old back button was a visually pleasing design. Its left side wasn’t just a standard, angular arrowhead — its angles were ever so slightly sloped, softening the shape just enough to suggest that going back would be smooth and instantaneous.
I never notice this design element, but it all makes sense. The effect may be subtle, but it’s thoughtfully designed and skillfully executed. It’s a hallmark of a company that makes the little details count.