The view is sometimes expressed that, when a DM puts too much time and effort into creating his campaign setting, there is a danger that it will "not make for a good game" because there will be too much detail, too much change of the players doing something wrong and out of keeping with the flavour of the world, the DM will be too persnickety about how things work in his precious snowflake setting, etc.
I think this is largely a myth, provided of course that we caveat this with the proviso that you have to assume good faith on the part of the DM; he's not a dickhead. In fact, I think deep worldbuilding is often what elevates a game to the next level of interest, because it gives the players a feeling that their actions are taking place in a wider and bigger context - they can ask the DM questions about the wider world and their own place within it, and receive coherent responses. And they can feel and experience a sense of history, making the setting feel realer, more "lived in".
You only need to read The Lord of the Rings to see how that works. Tolkien doesn't beat the reader over the head with the history of Middle Earth. He's not pedantic - there are no lectures. Instead, as you read the plot hooks you in, and you come across little snippets of information (Aragorn's song about Beren and Luthien, the journey through the ancient realm of Hollin, the barrow wights and their rumours of ancient kingdoms, and so on) which give you a sense of something profoundly ancient and real - it makes you feel as if Middle Earth, and most importantly the characters, are something more than just a figment of the author's imagination. That this feeling is entirely illusory, and that you are aware of that fact, does not make it any less important.