A second factor that also defies control is demographics.
But the school custodians are a special case; they run a system that has long defied rational control.
In some cases, the two become connected in ways that defy control, as Brazil has discovered.
The leg was like a separate creature, jumping fitfully, defying containment or control.
But there is still no consensus on how to restructure the system, a fiendishly tangled thicket of traditions, expectations and special interests that has long defied rational control.
Instead, he was put in a group home while his father was seeking to have him classified as a "person in need of supervision," a truant who defied parental control.
However, the process defied control by even the most advanced computers.
A6 American and Iraqi forces clashed for a third consecutive day as Iraq's vice president vowed to continue to defy American and British control of its skies.
These efforts were aborted in the course of the 983 Great Slav Rising in the Northern March, which again defied German control over the region.