If you, like me, tend to now design right away in Webflow, doing the main layout then graphic design then interactions, breakpoints and fine tuning, you end up with a perfectly working code that's very messy, especially on class names, so many exceptions, etc...
But it works, it can go to production (publishing).
Then when you have time, and since the design of, let's say section, is done, it's easy and quick to redo it from scratch with a better structure, classes and dependencies. Then erase the source one, filter and erase the unused classes in the style manager panel, and the site just got a bit cleaner. Do that progressively for all elements, you'll end up with an optimised and quite code-clean site. It appears Webflow still has some troubles to perfectly clean classes and code, but it's a hard task, it's preferable not to destroy existing code, and I'm sure it will get better anyway.
But in the end it's pretty great that you can improve your pages without having to start the site from scratch.