How much will you borrow for your next software project?

You have a business opportunity to make x amount of money, and then you estimate y of how much it will cost to build. You start the project if y < x. Typically, the conversation ends there.

There's one thing missing in the equation: The cost of maintenance z. A lot of factors can add to that, and this is where technical debt comes into play. If you cut corners, you add to it. If you design without your future needs, you add to it. If you don't automate, you add to it. Every manual task that blocks your change from going to production adds to it.

Always add an estimate of z with your original number. Put a number on how hard it will be to maintain the system in the future. The key here is to have a conversation with the stakeholder about this.

For every application, there is a different level of technical debt needed. If the software is part of your core business and the system will last forever, pay off your debt quickly, or you will pay interests for a long time.