There are many types of technical debt. It's something that accumulates organically in any real world project, because the real world doesn't care if your code is a paragon of programming excellence or not. It's expected, and simply part of the process, to develop technical indebtedness. The important part is controlling that indebtedness so that it doesn't cause major disruptions -- this usually means periodically cleaning up old debts and ensuring you have a robust system of monitors and failsafes. In a niche like finance, you certainly have to be more aggressive to ensure that no serious breakages or irrevocable indebtedness make their way into critical transaction code.