Baserunners can safely take a larger lead off Second base compared to First (or Third) due to the infielder positioning. Typically, First and Third Basemen play closer to their respective bases to minimize hits down the line, while the Second Baseman and Shortstop play deeper to cover more ground in the gaps. Leaving the Second Baseman near the bag for a pick-off opportunity would create a large hole in the infield defense and is usually not worth it. Hence, pick-offs happen mostly at First Base rather than Second.
Therefore, a baserunner can take a wider lead off Second Base, often about a third of the way down the baseline, making it easier to steal Third since there is less ground to cover. Although the catcher has a shorter throw to Third than to Second, the runner’s longer lead provides an advantage greater than the difference in time it takes the catcher to throw to Third instead of Second.