You will likely not get a perfect syntax right away. So you will need to iterate on it until you are happy with how it looks and feels, and doing it while developing the compiler yourself will naturally lead to a lot of unnecessary bugs and tech debt.

Alternatively, you iterate using a cheaper method and once you reach a point in which you are content with the syntax, you can consider writing a compiler for it.

You can also avoid iterating on the syntax so you can ship a compiler as fast as possible, but users won't like the syntax and won't use your language.