Assistance changes actual hit boundaries and miscalibrates the user's position model
Aliases: pointing assistance · hit boundary · model mismatch
What it is
A pointing-assistance model mismatch occurs when snapping, target expansion, prediction, or automatic correction changes actual hit boundaries while people still act from visible boundaries and direct position. Visually they may believe they selected A, while the system delivers the event to B or moves an object to a rule-based location.
Why it happens
People build an input-result mapping from visual targets, cursor hotspot, and prior action. Assistance rewrites coordinates, expands hits, or chooses candidates in the background, causing equal actions to yield different results in different regions. If activation is invisible, abrupt, or misaligned with intention, errors cannot be predicted or learned and feel like lost control.
Studying it
Compare direct and assisted conditions, recording expected versus actual target, correction count, reverse movement, learning, and trust. Include assistance entry and exit boundaries and deliberate choice of neighbouring targets; measuring only speed on successful assistance misses the mismatch.
Where it stops holding
No mapping is fully direct: ordinary tolerance and gain also change input. The problem is not assistance's existence but the absence of a stable, explainable model. Visible candidates, predictable operation, and suppression options greatly reduce mismatch.
Applying it
- Show current candidate, alignment, or actual hit range when assistance takes effect.
- Keep rules stable across objects and sessions, with a quick bypass or undo route.
- Track immediate post-selection changes by direction and region to locate conflict with position expectation.
Related
- Same group: C1.14.2 Assistance causes unintended attraction and wrong drops during drag · C1.14.3 Assistance must behave predictably rather than randomly
- Nearby: C1.12 Target snapping and sticky targets · C1.13 Area cursors and bubble cursors
- Search terms:
pointing assistance·model mismatch·hit boundary