Furthermore, a car necessarily encapsulates it's passengers while transporting them from one state to another and may allow one or more passengers to temporarily un-encapsulate while parked at a rest stop along an interstate highway. The car as an encapsulation of passengers has come under criticism by some for allowing this temporary un-encapsulation however others consider this a positive attribute and note the behavior is typically only observed shortly after crossing state boundaries and for a limited duration relative to the total time of encapsulation.