Continuous testing during a project's development is the most important indicator of whether you will deliver a relatively bug-free, quality product. Even post-deployment, periodic testing is important to see if something is about to or has already gone wrong. But even with all of this testing, unexpected failures, like total network collapses or denial-of-service attacks, are not a thing of the past. That's largely because of the complexity of today's corporate environments, where hundreds or thousands of devices are interconnected, each with bugs in their software making them vulnerable and each capable of random hardware faults and glitches. Testing every combination of everything is impossible, but that's no excuse for insufficient testing. Simply employing the standard testing procedures of exercising each function or product in isolation, and then again through the integration process may not be enough. Active testing on the whole system is the only way to prevent the out-of-the-box, seemingly impossible failures that are increasingly frequent.

Read more about the importance of testing:
- read the blog at IT-Director.com