Can't - is unable to; does not have the ability to; is forbidden to; is not permitted to
I don't like the word "can't" when it comes to a lot of things, particularly writing. The word "can't" limits, it hinders, and boxes in an individual's expression. In terms of writing therapy, "can't" can hold a writer back because they may be so focused on what they can't do according to the subjective opinions of others, and could potentially lose confidence in their writing ability.
Do you get where I'm going here?
I've read some books by "real writers" or "experts" in the writing industry, and while I appreciate the advice and understand a lot of it comes from their own personal experience, I still have an issue with an 'expert' telling me that I can't (i.e. "You can't write backstory in the first chapter," "You can't switch point of views in the middle of a chapter," "You can't write in the passive voice," etc).
While I believe it is wise to heed advice from experienced writers in order to grow in the writing craft, I think it is also wise to carefully pick and choose the advice that works for you as a writer. To take the word "can't" too literally could have you second-guessing everything you write.
For example, I remember taking a writing class where the Professor said "You can't write in the passive voice." I took this literally, and for years after that class I really believe that this piece of 'advice' stunted my growth as a writer. Suddenly, my work felt stilted, like I wasn't expressing what I really wanted to say, including my tone and voice. Have you ever experienced this?
When I finally broke free of the "can't," I found my writing expression was more organic, and I enjoyed writing a heck of a lot more. My philosophy is that there is no right or wrong when it comes to writing like there is in math for example. The only real question is, does your writing resonate with your intended readership? If it doesn't, then edit it!
Maybe I'm all wrong about this, after all, I'm not an "expert," just a humble writer who would rather remove writing barriers like "can't," in order to open up a world of possibilities and encourage fellow writers to express themselves authentically.