Just a Five Minute Job - A Home Improvement Metaphor for Tech Debt

One of the most interesting panel discussions that I participated in during Agile + DevOps 2018 centered around Technical Debt and what we can do about it. We found ourselves using a metaphor of home improvement projects a few times - especially the idea that you don't always know how big the task is when you start. With that in mind, I'd like to present a short recap of a recent "five minute" easy home improvement fix I found myself in.

The Problem:My girls share a room which contains one of the air returns for the heater. The grate covering this duct was no longer staying in the wall. This had led to at least one feline excursion into the ductwork, and now required that a trashcan or other large object block the grate to keep the cats away.

The Estimate:
This isn't a difficult fix. All I needed to do was grab my drill, zip in a couple of drywall anchors, drive the screws back into the wall, and done. Five minutes. Max.

The Reality:
First off, the grate cover is the wrong size for the hole. What I really should have done was get a new cover, or enlarge the hole, but one of those things would require spending extra money, and the other would require measuring and cutting additional bits of drywall. Both were out of scope.

After grate removal. Can't expand the hole to the left because there's a wall stud there.

My first fix was exactly as specified in the estimate. That worked fine, right up until I realized that the screws were now too short to properly open the drywall anchors. Okay, I'll get some new screws.

Then the screw on the right drove the drywall anchor straight through the sheet of drywall and into the five inch gap in the wall that I didn't realize was there.

Feline help from Romana the Time Kitty did not decrease the task duration.

No problem, I can go grab a couple of 2x4 ends, trim them up, fill the gap between the walls, and drive a 3" wood screw in there.

Which I did. Total time, between trimming 2x4 scraps, swapping out screws, removing busted drywall anchors, and oh yes, removing a helpful cat: forty-five minutes. That's 9x longer than my original estimate.

Yeah, this drywall anchor isn't going to work. I don't know why the original grate was set up with that screw so close to the edge of the hole.

To bring this full circle, it's the same issue with technical debt. You don't know what you don't know. Even so, technical debt must be handled. If I'd known I needed to trim up some lumber to fill a gap, etc, my original estimate would have been a lot more realistic. As it is, sometimes you just have to pull a task off the board, set aside 10x whatever your time estimate is, and hope this task is actually what it seems. Ever time, the set of unknown unknowns in your infrastructure will (hopefully) decrease. Every time I dig into a fix in this house I learn a bit more about it, and shrink my list of unknowns a little more. Eventually I'll know this place as well as the builder. I hope.