Why we should worship God when he doesn't need our worship?

There is a verse in Quran saying God created humans to worship Him.

But, God does not need our worship. Does it mean worship is a middle goal to humans so that they be trained for a higher goal?

What is the final goal of creating humans and nature and all things?

The verse is:

وَمَا خَلَقْتُ الْجِنَّ وَالْإِنسَ إِلَّا لِيَعْبُدُونِ

And I did not create the jinn and mankind except to worship Me.

Zariyat 56 (51/56)

There is no answers. Be the first answerer.