Here's why:
* "Talk at" implies one-sided communication. It suggests that the speaker will be talking *to* the listener, but not necessarily engaging in a conversation or listening to a response.
* It's informal and lacks politeness. "Talk at you" sounds abrupt and could come across as disrespectful.
Instead, consider using:
* "I'll talk to you later." This is the standard and polite way to indicate you'll have a conversation later.
* "I'll catch up with you later." This implies a more extended conversation or catching up on things.
* "Let's talk later." This suggests a more specific conversation about a particular topic.
It's important to choose the right phrase depending on the context and your relationship with the person you're speaking to.