Significance of parenthesis around a negative number in proofs

Question

I was going through this answer.

Why we need to generate 1+(-1) from 1-1.

What is the significance of bringing a parenthesis () around -1.

I am new to proofs . Sorry for poor math terminology.

Answer 1

When working with fields, the meaning of $a-b$ is $a+(-b)$. In particular, $1-1$ means $1+(-1)$, that is, the sum of the numbers $1$ and $-1$.

Answer 2

1+(-1)

What is the significance of bringing a parenthesis around -1?

Disambiguation and readibility. $\;$1+-1$\;$ isn't ambiguous; however, does $\;$1+-1+3$\;$ mean $$1+(-1+3)$$ or $$1+(-1)+3?$$

P.S. In each of these two expressions, the first minus sign is a binary operation, whereas the second minus sign is a unary operation: $$1--3\\1-(-3)$$