Many newcomers to this hobby fail to recognize that successful 3D printing takes planning. Because 3D printers use an additive process to create their builds, many complex structures require supports. These structural supports serve no purpose once the build finishes, and they can be removed from the print almost immediately. Many first-time designers assume the prints support themselves and fail to include lattices and rafts.
Those unfamiliar with 3D printing technology commonly assume that finished prints look exactly right from the moment they finish building. In truth, many prints require additional attention once you remove them from the build plate. The lattices and rafts must be removed and often you need to sand down the surface to achieve a smooth finish where the supports stood. This finishing process takes more time with thicker layers, while many of the thinnest layers require little sanding to achieve a smooth look.
The other major misconception behind 3D printing technology is that it is a good solution for mass-market manufacturing. Some designers want to print their designs on a large scale, even when they only have access to consumer units. Because of the cost of filament and the length of time it takes to finish a single object, 3D printing does not usually make sense as a large-scale manufacturing solution.
When manufacturing products, the fail rate of the production line makes a significant impact on overall cost. Desktop 3D printers often produce imperfect units, and it can take extra time to start over. Desktop and commercial printers help with prototyping and short-run production, but the cost of a print can add up quickly. If you plan to use a 3D printer for ongoing large-scale commercial production, you should first consider the cost of traditional manufacturing.