Organic traffic is great! Having it means you have a strong brand, one that's highly searched and sought after. Having high amounts of organic traffic actually boosts your paid campaigns!
But organic traffic is fairly unpredictable and its not very scalable. When it comes to organic traffic after you've done all the little SEO tweaks and have a strong posting routine on social media, you cant simply just "get more traffic" unless you look to paid.
Paid media is just better for selling products online because you can choose how many people you want to show the product too, and as long as you keep that cost lower than the income of people buying said product, you can continue the process until your business is where you want it to be!