What are the classic image-encoding mistakes?

Images that are too bland, too literal, static, or crowded onto one locus.

The failures that leave loci empty on recall:

• Too calm/realistic — a normal-sized rake lying still. Nothing to grab.
• Too literal — trying to picture the word instead of a vivid thing.
• No interaction — the image sits beside the locus instead of fighting it.
• Overcrowding — several images jammed at one spot.

Every fix is the same family of rules: one bold, moving, absurd image, physically interacting with its place.