I learned about the above bit of physics during high school baseball. One of our pitchers (Bubba), was one of very few people who could throw a knuckle ball. Even though we could tell it was coming because the ball wasn't spinning at all, it would dance around in the air and although it would come in slow, it was bouncing around too much to get a good, confident, swing at it.
When you see the ball spinning fast after it leaves a pitcher's hand you know it's probably coming in hot, unfortunately, you generally have only around 1.5 seconds to decide what you're going to do with the pitch, take a swing, or hope for a ball because it's all happening so fast. Think of a car blowing by you at 100 miles per hour. Many batters face pitchers who are also throwing pitches 100 miles per hour. It can be scary.
No other major professional sport is more difficult. That's why someone could make the All-Star game and only getting a hit on average one time out of three at bats (.333 batting average). That's a great goal for a batter to shoot towards.
Note: The picture below shows the grooves on a rifle which cause a bullet to spin.