Why is it very strange to update css on the server?

Question

CMS

I work through FileZilla and when saving changes, the styles remain the same. Moreover, if you update the file on the server, then new styles are loaded, if you update it again, then the previous version, and with the next update, the entire style sheet disappears and does not load, although it is available via a direct link from the browser. Browser cache is excluded because I knocked him out.
Some incomprehensible devilry, the first time I encounter such inexplicable behavior. What could it be? Can caching on the server what? But why then are the styles available via a direct link?

Answer 1

When changing css, for example, add ?v=2 so that the path to the file is like style.css?v=2