How do countermeasures differ from solutions?

Solutions are known to solve a problem and countermeasures are not.

A solution is better because it is the one fix to the problem, and countermeasures are several actions that need to be taken to counter the problem.

Countermeasures are measurable actions that always support final solutions to a problem.

A solution tends to sound final, as if the problem will never come back. A countermeasure can help make you aware that when circumstances change, a problem might come back.