Just as it sounds, "breach of contract" means that someone has not done what he contractually promised to do. But a breach of contract does not automatically mean that the contract is dead — that is, unenforceable.
To kill the contract before the project has been completed, there must be a "material" breach of contract. In other words, the breach is so serious that, in effect, there just isn't a contract anymore. There's nothing to enforce, because the contract has been so damaged it's beyond fixing — even if your standards for fixing it aren't very high....
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