Thread:ZagaNaga/@comment-4812386-20151104233958/@comment-4812386-20151108232732

Category:Catalog should only contain articles about the catalog itself (which does not include pages about catalog items, i.e. pages in the Catalog namespace). Pages are automatically put by the infobox templates in Category:Gear and Category:Navigation enhancers depending on the infobox template used, or on the parameters given to the template, so they should never be added to any of these categories manually.

Generally, you should look at a category's page in the Category namespace before adding a page to that category. Any information about which pages the category should contain will be there.