Which of the following is a design mistake that can make a part look poorly designed?

• A. Designing clearance holes as line fits
• B. Using standard thread types for all holes
• C. Adding many fillets that ease manufacturing
• D. Finishing all surfaces to high gloss

Answer: (A)

How a drawing communicates tolerances and fits can make a part look well designed or sloppy. For a hole that must clear a mating part, you need a defined diameter with a tolerance that guarantees the intended clearance. Designing clearance holes as line fits provides an ambiguous, nonstandard way to specify the feature, offering no explicit size or tolerance and often not aligning with common drafting practices. That ambiguity can signal sloppy design thinking and lead to confusion in manufacturing, which is why it tends to make the part look poorly designed. The other options tend to support good design outcomes—standard thread types improve consistency, fillets that ease manufacturing help production without compromising intent, and finishing all surfaces to high gloss is an aesthetic choice that doesn’t inherently indicate poor design.