The next question after you tell someone you’re doing a PhD usually is “Oh, in which area?”. In academic circles you’ll get asked more specific question regarding the project. You get to talk about your project hundreds and hundreds of times. And you might feel tired or bored doing so, which is understandable. But do talk to people about your project. There are positives to take home from doing so.
Talking to academics
As I said, it is different talking to academics about your project. They’ll want to know more and they’ll ask you targeted questions about your project. Such conversation will happen by the water cooler, during lunch, during meetings, or any other occasion in and out of the department.
With these talks you will get different reactions; some will be genuinely interested in your project and will ask more questions, give their input and give you new ideas. Other academics might just be doing it out of politeness, or just to break the ice (which actually thickens the ice).
In the first case their input and comments might spark some new ideas in your mind. They definitely view things differently than you. If you’re talking to older PhDs and higher (post-docs, lecturers or PIs) then they have more skills and knowledge than you. You might still be the expert in your field, but they have general research knowledge, and if they are in the same department with you, then they will have knowledge in related fields, making their comments even more valuable. In some cases they might even save you from making a big error in your design of experiments. Their comments should be always welcomed.
Talking to people outside academia
Now, talking to people outside academia might yield fewer interesting comments regarding your project. But that doesn’t mean you cannot gain from getting deeper into your project with non-academics. In fact, some of the most refreshing input I got was from people outside academia. They have the benefit of standing outside the bubble you’re in. This translates to them being distant from it all and being able to view the wider picture. You are standing too close to your project and it is normal that you might miss some things because of that.
Of course, there will be other times where people outside academia will swiftly change the conversation after you’ve briefly outlined your project as they won’t find it compelling enough to talk to. And that’s normal, as they don’t have the same professional interests as academics. But every once in a while you will get some great ideas by friends, strangers, family on your project.
So I would advise to talk to people; even if you don’t want to at that specific moment.