Tech debt is a phrase developers use with each other and it sounds like inside baseball. It is not. It is the most expensive thing on most small business websites and almost nobody paying for it knows the term.
What it actually is
Somebody needed to add a thing. Doing it properly would have taken four hours. Doing it as a hack took thirty minutes. They took the thirty minutes.
That was probably the right call in the moment. The problem is that the hack is still there, and now three more things are built on top of it, and the next person who touches that area has to work around all of it.
So the four hours got saved once and paid back nine times.
How you know you have it
A small change costs a surprising amount of money. You want to add one field to a form and the quote comes back at six hours, because the form is wired into three other things nobody documented.
Everybody is scared of the site. Your developer says things like I would rather not touch that. That is not laziness. That is somebody who knows the thing is held together with tape.
Updates break it. A normal WordPress update should be uneventful. If it is a heart attack every time, you have debt.
And nobody can tell you how something works. The person who built it left, wrote nothing down, and the logic lives in a plugin nobody recognizes.
The part that bothers me
You did not take out the loan. You inherited it and now it is in your name.
Somebody billed you for a website in 2021 and quietly handed you a maintenance problem that costs you money every year after. Nobody itemized that. It did not show up on the invoice.
That is the part I think is genuinely not okay, and it is why I care about how I leave things.
What I try to do instead
Every custom function goes in a file with a name that says what it does. Every field is documented. No mystery logic buried in a plugin somebody has to reverse engineer.
And when I inherit a mess, I clean up the part I am in. Not the whole thing, that is not what you hired me for. But the area I touched comes out better than it went in.
That is not craftsmanship for its own sake. It is so the next quote you get is honest and small instead of surprising and large.