Circular Error Probable.

The Circular Error Probable (CEP) is the radius of a circle within which half the bombs dropped by an aircraft are expected to fall.

In World War II the CEP for 'dumb' iron bombs was measured in miles - hence 1,000 bombers area bombing cities to hit a single factory.

The CEP of today's 'smart' laser guided weapons is three metres.

The CEP increases by 200% if the aircraft comes under fire.

Evasive survival manoeuvres reduce target accuracy. 

It's more likely to miss.

Nice analogy when you're taking aim at your Widget.

Or sniping at someone aiming for theirs.