Additionally, practitioners often misunderstand prevention. They ignore accumulated knowledge which has been learned across many fields. Prevention programs often reinvent the wheel rather than building on advances. Also, many prevention programs and initiatives focus on changing individual behavior alone while ignoring the family and community context. Practitioners can achieve greater gains by approaching prevention from a systems perspective rather than through attempts to reach only individuals.
Prevention is also widely underutilized until it is too late.
Approaches that ignore problems until symptoms require treatment can be iatragenic, that is, secondary problems can arise during treatment, such as unrelated infections and side effects from medication. Other possible secondary problems include excessive criminalization or overcrowded medical emergency rooms. Also, since recovery does not always equal health, those who are survivors or victims may never reach the state of health they had before an incident occurred. Finally, approaches that address problems after they have occurred tend to be more expensive than preventive strategies. Effective prevention requires proactive strategies.