We all Indian whenever we do any activity, we worship Lord Ganesha first, and then proceed with that work. That is why we worship Lord Ganesha before anybody else, there is a story about that concern.
One Day Ganesha and his brother Karthikeya were arguing about who is best them was the most knowledgeable. Listening to this, Parvathi and Shiva, wanted to test them. They told them that the one who goes around the world and comes back first is the most knowledgeable. Karthikeya immediately started his journey and went around the world on his peacock. When he came back, he saw that Ganesha was still standing near his parents. When Karthikeya asked him, Ganesha went around his parents, symbolizing that his parents were the whole world for him. Seeing this, Lord Shiva declared that Ganesha was the most knowledgeable. So they wished to Ganesh will be first (PUJANIYA) to all peoples when they pray or puja.
There are many other stories are also famous, this is one of them.
