The First Slip | Brett Castellaw

It was 2019. A client called in a panic: their entire network was crawling. Latency was through the roof, video calls were freezing, and file transfers were taking forever.

I jumped on the ticket. Ran the diagnostics. Ping tests came back clean. Bandwidth looked fine. The user's machine? Perfectly healthy.

So I closed the ticket with a note: "User error. Suggest they reboot their router."

Two days later, the client called back. The problem was worse. Their entire sales team was locked out of the CRM during a critical quarter-end push.

I went onsite. And there it was: a single cable in the server rack, rattling loose in the termination block. The pin had been slowly working itself out, causing intermittent packet loss that only showed up under load.

Four hours of downtime. A frustrated client. And my reputation as the guy who "just knows" took a hit.

The Lesson

That mistake taught me three things:

Never trust a ping test alone. Latency can be intermittent. You need to look at the whole picture.
Physical layer problems are the hardest to diagnose. When software looks fine, it's time to check the cables.
Admit when you're wrong. That client forgave me because I owned the mistake and fixed it for good.

The Checklist

Now, before I close a single ticket, I run through this checklist:

Check the physical layer first (cables, ports, switches)
Run a full network diagnostic, not just a ping test
Ask the user about the exact moment the problem started
Test on a different machine to rule out user-specific issues
If it's still a mystery, escalate it. Don't guess.

Every craftsman has a "First Slip." Mine cost me a client's trust for a week, but it made me a better technician. Now I'm more patient, more thorough, and I never close a ticket without double-checking my work.

What's your First Slip? Share it in the comments, or check out the other stories in this thread. We're all better for the mistakes we've made.