I see it happen all the time. Average Joe / Jane set up an online store, sell decent products, but expensive ones – most of the time super niche products.
Joe / Jane have low number of followers on their Facebook / Instagram page, but keep posting irrelevant crap with many hashtags in them, but little to no reaction from audience cause they don't put a marketing budget behind the posts.
When you sell something above let's say $70 USD, you're not going to get sales if your e-commerce experience and marketing isn't perfect. The number one most important criteria is to get TRUST from your target audience. Nobody is going to spend hundreds or thousands of dollars on a store that isn't trustworthy. A good way to build trust is social proof. Put money in interesting ads to get more followers – and make sure there's a link to your store in these ads. I can grow a Facebook page to 100K followers in a month with low budget. Once you get 100K followers, it's much easier to get trusted for sales.