Common miss
Direct answer
The common mistake is treating Surface and subsurface indication logic as a loose phrase instead of a rule, condition, or field decision with consequences. Surface and subsurface indication logic is one of the core study areas for Weld Discontinuities and NDE Practice Test. If you miss this area, review the explanation, tag the weak concept, and drill nearby topics such as Discontinuity naming, Defect versus discontinuity, VT, PT, MT, UT, and RT selection.
How to use this answer
Read the answer once, then prove it by choosing an answer in a practice question before looking at the explanation. If the miss repeats, tag the domain as Study module and drill a smaller set before returning to mixed practice.