Here are some reasons why some people thinks that Amazon Affiliate Program is not good as it used to be:
1. Late last year, they dropped the cookie lifetime from 30 days to 1 day.
2. The starting affiliate pay is only 4% (although that can be increased to 6.5% based on how many sales volume you can generate for them).
3. There is no one central affiliate portal where you can promote products for other countries. That is, if you singup for amazon associates US (you will know that when you have an id ending with -20), you won’t get any product details from the UK).
What if you were to promote products for the UK market? Well, you would have to signup for amazon associates UK. Not only will you get a different ID, but also different payment structure.
Point 1 is probably the main issue for affiliates. Most affiliate programs pay at least 10% with a cookie of 30 days. Many of our earnings in affiliate programs are going to be made from purchases 10 or 30 days down the line after a user has clicked the link. So cookies are an important part keeping track who refered customers to the merchant, so affiliates can be paid for referring customers to their site.