Here i have some questions . How many(average) articles you submit? What is the number of the directories that you submit? And may be the most important question - after what time you feel the results?
I've submitted around 40 pver the past years. I submit to 3 directories. I generally start to see visits from either the article site or site that have published it within 2 weeks. Good Luck
After approval I have an increase in traffic anywhere from 2-4 weeks then a slight drop off after 8 weeks - telling you that you need to keep publishing to keep the traffic up. If you can get your article to be one of the top ten for you keywords you'll keep traffic coming from that article for many months. That's the value of a good article.