Technical debt
The accumulated cost of past shortcuts in a codebase. It charges interest: every change in that area takes longer.
What it tells you about a developer
Candidates who discuss tech debt as deliberate tradeoffs, naming the shortcut they took and when they repaid it, show senior judgment. Returning to maintain and clean up old repositories is the profile-readable version of the same habit.
Under deadline pressure, teams take shortcuts that work today and slow everything down later. That accumulated drag is technical debt. Paying it down means spending engineering time on cleanup that produces no visible feature. That is why it becomes a negotiation between engineering and the business.