Why do people use brackets, or parentheses as our American friends would say, in the written word?

We don’t use them verbally, other than an aside perhaps. For me, brackets are rarely used to explain some background detail, like something you might see in a footnote.

When I see content in brackets, I think it reduces the power of what you’re trying to say.  It feels like you know you should write less, but don’t have the courage to edit down, so you put your potentially superfluous text in brackets. Or maybe you just want to separate clauses out.  For that you could use the hyphen – or is a dash? – to get your reader to pause.

Remove the brackets and let your words go free, or lose them altogether (or not, as the case may be).