“…Maintenance and spare parts availability 9 [27,29,50,58,64,73,89,90,114] Constant quality improvement 1 [6] Quality assurance 8 [3,5,6,29,50,58,67,71] Costs Competitive value 1 [91] Low material costs 2 [38,92] Low break-even points 7 [8,10,27,29,38,57,93] Economics of scale and scope 5 [7,27,32,38,54] Employee Qualification Lack of skilled employees 27 [5,26,27,30,31,[33][34][35]37,39,41,47,50,54,56,58,…”