Secondary consequences are not paid attention to as long-term knowledge may not spontaneously be recalled. Past secondary results from primary effects on physical tangible objects are not noticed till after the incident occurs. This reduces the person's ability to prevent negative secondary consequences. Common errors may be warned ahead of time with preventive rules put in place. Anticipating all errors are difficult. Having understanding caregivers who can rescue the person when a negative effect occurs is important. The risk involved must be weighed up with the person's freedom.