DMOZ is created for people to find information.
In contrast to search engines this information is grouped by subject (which we call categories).
For each subject we list a number of websites.
In the beginning, when the internet was small, DMOZ tried to list all worthwhile websites but during the years we have learned that with the fast growing internet this is and never will be possible. As a result well developed categories with many listed websites will get less attention than small, underdevelopped or new categories.
DMOZ does not provide any service to website owners / developpers. It never had and it never will have.
DMOZ might have had, and even still have, some effect on websites, like SEO and SERP. But such effect isn't and never was our intention.
That is also why you can not "submit" a website. "Submit" would inlcude the meaning that DMOZ is obliged to do something with the submission. The only thing people can do is "suggest" a website. When DMOZ started it was the intention that people would suggest websites they found on the internet. We did not anticipate on the fact that people would massively start developping websites and suggest their websites. "Suggest" can be seen as "Hi DMOZ editor, I have encountered this website on the web and think it is a usefull resource which I would like to share with other people". DMOZ can use those suggestions. But they may also ignore them. We are interested in builing categories not in listing individual websites.