With a major responsibility of part performance on its shoulders, Design for Assembly (aka DFA) spells efficiency for industries worldwide. A frequent in electro-mechanical industry, Assembly is no alien to industries like sports, fast fashion and the like. While industrial specifications might call for customization, standard design practices for Assembly parts are (and, should) be adhered to.
Study of the varied material available reveal the following common design practices (or, guidelines) for efficiency:
1. LESSER THE BETTER
A rule of thumb leading industries swear by--aim for simplified and minimal parts in a design. With less room for erroneous/defective parts, simplified fabrication & automation, less requirement of specialized equipment, lesser inventory needs; a simplified production spells optimization! Moreover, in situations where design needs reconsideration, designer can easily go through a design part by part without the hassle of a complex amalgamated product. In most cases, 'minimum' can be obtained by opting for an alternate material considering 'lesser' time to fabricate (or, produce).

2. STANDARDIZATION NEVER STOPS TRENDING
An extension of the above point. Using (and, reusing) a select set of parts of materials which can be incorporated into any design results in a nominal requirement of inventory. Further, standardizing end-to-end handling practices and assembly itself, would help one deliver superior quality products at minimal cost.
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