The product development process begins with an idea and ends with manufacturing. Between these two steps are the design, engineer and prototyping phases, where companies test their products prior to manufacture. The objective is to make sure it is fit for the customer and for purpose. Whenever errors appear, the prototype is tweaked and tested again.
TL;DR (Too Long; Didn't Read)
Prototyping removes errors in the product before it goes to manufacturing, but it adds serious dollars to the development cost.
Advantage: Testing for Functionality
Just think of the manufacturing nightmare companies could have if they send their products to production without creating a test part. That's the biggest advantage of making prototype parts: to test for things like function, fit and durability. Making test parts helps engineers identify areas where a particular product can be improved or if it has any flaws. In addition, prototyping can provide an opportunity to get feedback from the customers themselves about the product to see how it fits their needs, including any requests for additional features or changes to appearance to make the product more user-friendly. In the end, analyzing prototypes helps dictate design changes.
Advantage: Speed and Quality
Another advantage of prototyping is the speed at which it can be done. Rapid prototyping systems, such as 3D printers, can create prototype parts in hours. This puts parts in the hands of designers and engineers quickly, so design changes can be made faster, sending products to market faster. A side benefit from this speed is that the company can quickly determine how to improve the product's quality during rapid development, meaning the end product will have fewer costly flaws to correct. Rapid prototyping systems are also able to make parts in virtually any material. 3D printers can create parts in all different types of plastic, while selective laser sintering systems can make parts in fully dense metals.
Disadvantage: Added Development Costs
Although prototyping systems are becoming smaller, more sustainable and more affordable, they still present an additional expense for companies. The biggest 3D printer companies, for example, have developed small, portable, desktop rapid prototyping systems specifically for smaller businesses. Although they're cheaper than other systems on the market, they still cost upwards of $20,000. Companies can outsource for their prototyping needs, but those costs add up as well.
Prototyping helps companies print parts for functional testing prior to production. But despite advances in technology, many prototyping systems can't exactly create the design. Even the most accurate 3D printing systems, for example, create parts to within 0.1 mm accuracy. While this is almost perfect in terms of part accuracy, it's still off from what the part's final dimensions will be. Prototyping systems also have difficulty creating parts with thin walls or fine patterns.