High-mix, low-volume (HMLV) manufacturers have faced extensive challenges when it comes to automation. The need for detailed planning, programming and jigging that comes with most automation systems (especially robotics) makes them fundamentally inflexible in adapting to the varied parts, processes and work methods that HMLV manufacturers need to get the job done.
This leads to a reliance on skilled human labor, but there are three problems here: skilled labor is scarce and only becoming more so, skilled labor is still prone to the same faults of fatigue, boredom and inconsistency that every human being has, and attracting skilled labor requires better pay, better benefits or better quality of life that can all - with the wrong systems - make production fundamentally unprofitable in a globally competitive economy.