"To each is specialty." I do not understand

-"Write about what you know. To each is specialty*. It is important to stick to the themes defined in the additional charter of your site. Don't scatter on topics outside the scope and be faithful to the editorial line defined at the beginning" - *I read it in an article and I do not understand what does it mean. Can anybody explain 🙏?

Solution 1:

This sounds like an attempt at referencing "To Each his own"

From Merriam-Webster:

used to say that other people are free to like different things

In this case - it means you are free to write to what your specialty is. This is how I would understand it, given the context.