I believe that a browser should have to make no more than 3 clicks (Main cat, Sub cat, Listing) to get from the homepage to a site that they are looking for. So I don't think there is a need for 3rd or 4th level categories. The problem with this, is that there will either be a lot of listings per category, lots of root categories, or lots of sub-categories that might get slightly off topic. So what do you all think?
There will always be a need for a 4th level category. You are helping a user find what they need more easily by having more categories IMO. For example Sports > Motorsports > Formula 1 > Tracks > History/Tickets/Evenets etc
I personally think three levels is more than enough for a paid directories, 20x20x20 is a 8k categories.
Simple. A directory should have listings in all categories. All categories should be sub categorized as needed. No matter how many levels you end up with, just make sure they're all full of good content. If your subcategories get off topic then either they need to be moved or you may need to consider a new top level category. Ignore PR when doing this... I recently moved categories in LinksQuitters Directory because it made sense. PR went away for those moved categories but I really don't care. We want an orderly directory and that's what we're going to have.
Tracks and Venues would have to include motor, motorcycle, horse, greyhound and probably other tracks. Very difficult to find what you're looking for. Better is Sports/Motorsports/Tracks and Venues, IMO.
Sports > MotorSports makes sense for everything related to MotorSports. Sports > Tracks and Venues could mean more than just MotorSports, it could include horse-racing, boat racing, dog racing... and venues just gets even broader with football arenas and such. Sports > Tickets and Passes has the same problem as "Tracks and Venues". It could contain tickets for hockey games, soccer, football, tennis and on and on as well as MotorSports. No matter how you look at it, you will need to put a lot of thought into your sub categories and sometimes you will need to rearrange things.
I don't think people will mind clicking more to find the specific category they are looking for. They will more likely not be happy if the links in that category waste their clicks.
Yes I understand, I am figuring that if someone goes to stubhub with looking for ravens tickets, they don't mind all the other tickets.
i think categories will be a forever and never ending change and reorganization all throughout a directory's lifespan. It just seems that no matter how many you have, something else can be added, changed, swapped, switched, condensed down. I say start with a base only a few levels deeps and work from there. You'll never know how deep down you'll wind up, but trying to keep it all together and organized is most important.
Even if a category is too deep but has some related content and keywords - it will make the "top SEO category"