My breadboard power supply died and I found the real issue was my own wire colors
Last Tuesday I was testing a simple LED flasher circuit on my bench and the whole thing just went dark. The 5V rail on my bench supply dropped to zero and I spent two hours swapping out caps and regulators before I looked closer at the actual wires. I had used red for ground and black for positive because I grabbed the wrong spool from a drawer back in January and never labeled it. Once I rechecked every jumper by tracing each one with a multimeter, I found three joints I had soldered backwards on the perfboard. The supply was fine the whole time, my color coding was the real failure. I rewired everything with proper red and black and it fired up on the first try. Anyone else ever trust their wire colors too much and chase ghosts for way longer than they should? How do you stop yourself from assuming the cheap part is the culprit? For me it was six dollars worth of wire and two full evenings lost, but at least I learned to label my spools now.
The tricky part is that your brain fills in what it expects to see, so once you "know" red is positive you stop actually reading the wires. I've started doing a quick continuity beep test on every new run before powering anything up, takes ten seconds and it catches stuff my eyes miss. Also labeling spools with a piece of masking tape is stupidly cheap and has saved me way more than six bucks in lost time.