It's difficult to determine the exact reason why your coworker says "no because" when revisiting a topic in conversation without more context, as individual behaviors and communication styles can vary significantly. However, there are a few possible explanations for this behavior:
Defensive response: Saying "no because" might be a defensive mechanism used by your coworker to protect their ideas or viewpoints. By starting their response with "no," they may be trying to assert their position or protect themselves from potential criticism.
Clarification or correction: When revisiting a topic, your coworker might be trying to clarify or correct something that was said earlier in the conversation. The "no" in their response could indicate that there was a misunderstanding or a misinterpretation of the previous information.
Asserting a different perspective: By saying "no because," your coworker could be introducing an alternative viewpoint or adding to the discussion with a counterargument. It could be their way of offering a different perspective to the topic.
Habitual response: Sometimes, people develop certain speech patterns or phrases that become habitual without much thought. It's possible that your coworker has formed a habit of starting their responses with "no because" even when it might not be necessary.
Asserting boundaries: Depending on the context, saying "no because" could be a way for your coworker to assert their boundaries and indicate that they are not interested in discussing or revisiting a particular topic.
To better understand why your coworker uses this specific phrase, it might be helpful to observe the context and the tone of their responses. It could also be valuable to have an open and non-confrontational conversation with them, expressing your curiosity and desire to better understand their communication style. Keep in mind that people communicate differently, and there could be various reasons behind this behavior.