Not necessarily, but a blog is really the best promotional tool. With that said, you can always use methods such as PPC or advertising to promote a product. This is another popular method to grow in affiliate marketing. For me, the best way to make the most out of affiliate marketing opportunities is to have a blog. Learn how to start a blog here.
An affiliate marketing program is a lot of work, and in most situations there's a lot of competition so you're not going to be bringing in money immediately. Business owners and entrepreneurs suppose that all you need do is setup a site and choose an affiliate to associate with and then just let it run its course. But according to Three Ladders Marketing, only 0.6% of affiliate marketers surveyed have been in the game since 2013. That means that affiliate marketing takes time and effort to build and make money.
In April 2008 the State of New York inserted an item in the state budget asserting sales tax jurisdiction over Amazon.com sales to residents of New York, based on the existence of affiliate links from New York–based websites to Amazon. The state asserts that even one such affiliate constitutes Amazon having a business presence in the state, and is sufficient to allow New York to tax all Amazon sales to state residents. Amazon challenged the amendment and lost at the trial level in January 2009. The case is currently making its way through the New York appeals courts.