I did do daily drawings for over a year. A lot of basic fundamental stuff, like cubes, spheres, cylinders, etc. In between I would draw a lot from pictures. Trees, landscapes, animals, faces, still life ( pencils, cups , etc ), all using these shapes.
These many 15 min – 40 min drawings allowed me to practice multiple techniques, until I figured out what worked for certain things.
Like combining cross hatching with following the contour of the shape, in ink.
When to best use stippling vs hatching vs blocking in.
That kind of thing.
In repeatedly drawing certain basic shapes to flesh out objects I started seeing objects that way.
These drawings all just happened in the space of a couple of days. most of them straight out of my imagination. It felt like with no effort and completely out of the blue. But looking back, it is a result of over a years worth of work.