I give all our CAD recruits a quick draughting test immediately after their interviews, to date 75% fail this very simple test for many of the reasons already given, plus a few more.
1. Draughting by eye; I've been amazed by the number of applicants who can't draw a line of an exact length, instead they watch the coordinates in the taskbar until they get it almost right. They usually fudge dimensions to cover-up.
2. Failing to use snaps correctly; a real pain when trying to hatch boundaries or dimension.
3. Not inserting mapping xrefs at 0,0.
4. And in 3D modelling terms, copying objects within a drawing rather than blocking & re-inserting them.
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