I recently mentioned the classic Fleischer Superman cartoons from the 1940s, which brings up an interesting bit of Superlore:
The Fleischer cartoons were also responsible for Superman being able to fly. When they started work on the series, Superman could only leap from place to place (hence “Able to leap tall buildings in a single bound” in the opening). But they deemed it as “silly looking” after seeing it animated and decided to have him fly instead.
Now it’s Marvel’s Hulk who leaps tall buildings in a single bound.