The problem is, of course, that so many people do. You have a cute saying, and Basic Writing Questions fill up with new writers trembling in their boots because They've Done Wrong.
Same with the "adverb-rule". Same with the word "was". Same with passive-voice, which leads to people avoiding perfectly valid writing that isn't even passive. The rules appear writ-in-stone because of some cute saying that we all repeat because they are easy to remember and quick to fire off.
It is weird that faced with stuff like this people in general abandon all common sense. If you read a lot you discover that published writers do all kind of things that they shouldn't. Publicly available interviews with published writers reveal that everyone has a different approach.
There is no particular way you have to write, no magic tricks, no system, it is just about getting down a story somehow or other and making it as good as you can.
I have published sixteen books ( eight novels) and each one has required a slightly different approach. When asked I will come up with something which approximates my method, but so much depends on how things are going. I have got some books ninety percent right first time and others have involved total rewrites.
What you have to do is to give yourself permission to write - whatever that means for you. For some people the biggest issue is finding the time, for others it is the self belief, and for another group it is accepting that it isn't necessarily going to be work of genius. Sometimes giving permission means accepting all of those things. For me writing is about suspending disbelief, in the story, character and my own capacity; it is about saying -' sod it, do it and worry about it later.'
That works for me - most of the time...but it isn't a rule.