Clickbank can be said as the hub of digital products. What matters is the quality of the traffic (are they the sort of people who would actually be interested in buying your affiliate products and have the means to do so?) and the quality of your site (does it do a good job of getting visitors interested in your affiliate products and convince them to actually click through and make a purchase?).
You've may also choose to search for offers that work for mobile traffic, because if you're doing Facebook ads for example, and you're sending traffic that's coming from mobile and the website doesn't handle mobile traffic really well and the page looks all distorted, then you're not going to make any sales.
You can actually email the vendor and say, Would it be possible for me to have a review copy of this product because I would like to promote it?” Sometimes they will let you have access to the product, but that's usually when you're an established affiliate.
But when you start digging and if you watch their sales video on their website you soon start to realise that their claims of making $500 to $1,200 a day with just 5 minutes of work clickbank for beginners are complete BS. I am sorry, but I have been involved with affiliate marketing for a few years now and I have yet to find a program that can make you money with little or no work.
If you've listened to much of my training, when it comes to showing you how to find affiliate products to promote quite often I personally refer to the Clickbank Marketplace The reason I do this is because Clickbank approves virtually everyone (unless you are from Nigeria or some other country outside their approval zones), and they have an amazing selection of products to promote with high commissions.
But, you should be careful while selecting the products that you promote on your website, since some of the products may not be genuine and useful as they make out to be. This is just to ensure that your visitors don't get cheated by some useless "digital" products.
Many millionaires have been made through the affiliate Clickbank program because they decided they wanted to. If you go to Clickbank, grab a hoplink and throw it on some free advertising I can almost guarantee you will never make a penny and more than likely never make enough to reach payout.