One would think that after nearly three decades of additive manufacturing (AM) technology using various polymer materials, we would be further along than we are currently. In the 1990s, most of the parts obtained through the stereolithography (SLA) or selected laser sintering (SLS) process were of the touchy-feely variety. You could get a good idea of what the part would look like and if the dimensions were suitable, but that was about it.
While there have been some advances in materials, machines and processes over the past 15 years, the number of thermoplastic resins offered for 3D printing remains a problem. Compared to the number of thermoplastic resins in the mainstream plastics industry (as many as 77,000 different resins, according to some estimates), the options available for 3D printing are quite small. That is a limiting factor in the fabrication of actual end use parts in a production environment.