Kubrick was remarkable in his singularity as a filmmaker.

There is a fantastic 1 hr BBC documentary from the mid 2000's called 'Stanley Kubrick's Boxes' in which the documentary crew is given access to Kubrick's estate and warehouses after his passing. They examine the contents of the boxes of research and pre-production material that Kubrick accrued over several decades when crafting his films. The lengths he went to flesh them out are stunning.

The takeaway is of someone with a singular ambition and extreme thoroughness when planning their films. It's been immensely inspiring to witness just how intently a creator can focus on crafting their work. I strongly recommend it.