What is the purpose of queueCount inside VkDeviceQueueCreateInfo?

https://www.khronos.org/registry/vulkan/specs/1.0/man/html/VkDeviceQueueCreateInfo.html

What I currently do:

Find a device that has a queue that supports graphics and surface.

I then find the index for the graphicsQueue and the surfaceQueue. In my case they are the same, but I think they can be different as well.

Now I have always set queueCount to be 0 and I didn’t run into any problems so far, but I probably should set to the queueCount to VkQueueFamilyProperties.queueCount.

But now I am wondering what it actually does? Does a higher queueCount indicate better performance?

It seems like that I can not delete posts.

Here is the answer https://stackoverflow.com/questions/37571757/what-is-the-purpose-of-queuecount-inside-vkdevicequeuecreateinfo