Technical debt is the consequence of poor system design and architecture which can happen when features are done gradually in an adaptive environment. The Development Team should be careful with it and repay it with continuous refactoring.
Refactoring is improving the code without changing the external behavior. If the technical debt keeps increasing because the team doesn't refactor or have a poor definition of 'Done', development will become harder day after day and
it will slow down the progress on one hand and even create problems for releases on the other hand.