That rainbow spinning wheel (whatever you might call it) is a common macOS wait cursor. It’s triggered when an application doesn’t respond for a few seconds and signals that you should wait before giving the app more instructions.
Why is my Mac cursor rainbow?
The spinning rainbow wheel is a common macOS wait cursor. This wheel comes up when an application that you’re running doesn’t respond for a few moments.
Why is my Mac cursor spinning?
The spinning wheel of death can appear when your Mac is using virtual memory and the storage space is limited. The more physical RAM you have, the less your Mac will need to resort to virtual memory. So installing more RAM can fix the spinning color wheel problem.