I'm not sure what you're talking about.
Editors look for good sites to list in the directory.
Anyone can suggest a site. Even if it's their own site. When an editor is looking for sites on a particular topic, they can see all the suggestions made to that category. If those suggestions are helpful, they're used, for all they're worth. And when all the help (if any) is drained from a suggestion, it can be discarded.
So you can suggest your site, but only an editor can actually review it and (if appropriate) add it to the directory.
There's no rule on when people can work to improve the directory. It's not too late to suggest a site to a category, even after the editor has built it up from nothing by Google searches. It's not too soon to suggest a site, even though an editor may not visit the category for another year. It's not too soon to review a site, even though it's never been suggested. And it's not too late to review a site, even though it was suggested two years ago. Everybody works when they can: every little bit of constructive work helps.
