As a writer, you should also be striving for continuous improvement. I know I do. Even best-selling authors are very likely trying to write better all the time. If they don't, they won't stay best-selling very long (this is, I think what happened to Tom Clancy; he got lazy).
For example, after my first couple of novels were published (Hammer of Thor and Agent of Artifice), just for fun I went to this word cloud website and made word clouds from the edited manuscripts. And here's what I found:
|Word Cloud for Hammer of Thor
|Word Cloud for Agent of Artifice
And I noticed that I apparently used the word "looked" a lot. So now I'm on a mission to eliminate it by instead of saying "He looked" saying "He glanced" "He stared" "He scowled" "He squinted" pretty much anything but "looked."
Then my writers' group told me I should avoid adverbs. So I do that, too.
Lately I'm on a mission to avoid the word "seemed" because I have noticed I use it way too much. I don't have to say "The room seemed charged with her power" (a line from Gods of Strife) but "The room was charged with her power."
If you aren't striving to improve you're writing (and I don't care how many books you've sold) you aren't going to get better. And all the writers who are working hard to improve their writing are going to be a better writer than you. And you'll be left in the dust.