I've had many Cat-5 cables, phone handset cables, and in the past, straight phone cables break the latch at the connector. That means that it becomes easy for the cord to pull out. To recover it, you need to replace the cord, or if you're more technical, you need to re-terminate the cord – seldom worth it unless it's a long network cable.

I designed this after I lost a phone handset cable at work, and I got fed up with the issue. These are quick and easy to print. You just slide it in behind the connector, then plug it in. It holds the connector in place - no cord replacement (MUCH less expensive) and no re-termination (MUCH less work).