Defects cause lateness.
The more defects code has the more time and effort it takes to get it to done. This seems a self-evident truth. But beware! The Causation Fallacy says it is not easy to know what is cause and what is effect. If a feature misses its deadline pressure often builds to ensure it doesn't miss the next deadline. And under pressure people don't think faster. Extra pressure usually increases the likelihood of defects. This suggests
Lateness causes defects.
So do defects cause lateness, or does lateness cause defects? Or do they rotate around each other like partners on a dance floor?