There is zero follow up - no prototyping, no CAD files, no R&D, no clinical trials, no betas, no execution - it goes from nebulous "idea" straight to the legal department.
I suppose that depends on how pervasive patent trolling has become.
But yes, I would say that the development of the vast majority of inventions worth protecting would necessitate more than some scribbling on a bar napkin.
If the process begins with some vague "inspiration" about where an invention may lie, and then promptly ends with a call to your lawyer - no feasibility testing, no fleshing out of the concept, no iteration of thought, I would say that the patent system is fundamentally broken.
Is that uncommon?