Forces describe what an effective solution for a problem must consider. An effective solution must balance the forces of a problem. A solution may not perfectly address all the forces. There might be consequences of implementing a solution that balances the forces, however, the benefits of implementation must outweigh the liabilities. For instance, for a system that makes multiple calls to another system on network, a force can be the need to improve application performance. You can solve this problem by batching the calls made by the system. This approach will introduce the liability of increased response time and storage space overhead but if configured precisely to balance response time, performance, and storage, it will adequately address the force without adding high liabilities.

You need to evaluate whether a pattern addresses the forces applicable to your problem, evaluate the benefits and liabilities of applying a pattern to your problem, and validate whether the liabilities arising out of application of a pattern are within acceptable limits of the requirements.