Companies that enter into a contract are expected to abide by the terms. Unfortunately, there are times when one side won't do what they are supposed to do. This is considered a breach of contract, which can lead to legal action.
Businesses should always ensure they fully understand what obligations they have when they sign a contract. Everything in the contract, including specific actions and time frames, must be complied with. Typically, a breach of contract lawsuit isn't going to come about when just one issue creeps up. Most of the time, the company that isn't breaching the contract will try to work things out with the other company.
One thing to remember is that if you are going to take action over a breach of contract, you have to show that you suffered damages due to the breach. When you do suffer damages, the breach will likely be classified as material. If you don't suffer any damages, it will be deemed immaterial.
The wording of the contract plays a part in how it is viewed. If it clearly spells out that the terms aren't bendable, you might have a better claim. For example, if you need a shipment at a certain time and include "time is of the essence" in the contract with the delivery deadline, it would be a breach of contract if that shipment showed up after that time.
Most contracts will have terms regarding what will happen if parts of the contract are breached. This is where you will turn to find out what is possible. If you can't get the other party to abide by that either, you might decide that a lawsuit is in order.