Do you have any difficulties with suppliers? For example, PetroChina/Sinopec is a supplier, serving drivers (gasoline). Drivers don't have to get off at the gas station as long as they spend money on gasoline. What does PetroChina/Sinopec need to do? Since the establishment of the national project, geological exploration, drilling, mining, refining, storage, pipeline laying, refined oil pricing, etc. (I'm not in the oil industry, I don't remember the details), it takes dozens of departments and hundreds of cities across the country, and it takes more than ten years to complete a project. You said that this supplier is not difficult and the process is complicated.
Want to know all about cloud computing, just like want to know the complete oil operation (from field exploration to gas station oil gun), or chew slowly from scratch, or find a link that interests you to cut in and expand your learning.