A poor description is quite useful when used in real time: during a small window of time after the crime, within a small radius.<p>Descriptions are frequently sketchy like this. You hear them on the news daily. &quot;Middle-aged white male wearing jeans and a ball cap&quot;. If that&#x27;s all you have and don&#x27;t act on it immediately at the time and location, its usefulness evaporates.