Okay, so imagine you have a basket of different colored candies. You have red, blue, green, yellow, and orange candies. Each color represents something different, like red candies are boys, blue candies are girls, green candies are adults, yellow candies are kids, and orange candies are elderly people.
Now imagine you need to separate all of the candies into separate piles based on their colors. You can do this by just separating them by color, but it might take a long time if you have a lot of candies.
But if you have a friend help you, you can separate the candies a lot faster. Your friend can take all of the blue candies (girls) and put them in a separate pile, while you take all of the red candies (boys) and put them in another pile. By working together, you were able to separate the candies faster than if you had tried to do it alone.
This is kind of like diversity gain. When you have a diverse group of people working together, they can use their different skills, experiences, and perspectives to accomplish a task or solve a problem faster and better than if everyone was the same. It's like having a friend help you separate the candies more quickly because they have a different perspective and can see things that you might miss.
So when we talk about diversity gain, we're talking about how having a diverse group of people working together can help us achieve our goals or solve problems more efficiently and effectively. Just like how having a friend help you separate the candies can get the job done faster, having a diverse group of people work together can help us get things done better and faster.