This question is probably the most urgent, and in fact, the answer is simple. Reason # 1: Google "likes" fast pages.
If you want to gain organic traffic, you can work with content on your website. However, if you want your website to rank high on Google, page load speed is of prime importance. If the site does not appear in at least the first 10 results, you are not likely to attract organic traffic.
So why does Google "love" sites with a high loading speed?
Tip: If you have experience in eCommerce, there is a high chance that you are familiar with the term bounce rate. The bounce rate shows the percentage of all sessions on your site in which users viewed only a single page and triggered only a single request to the Analytics server. A high percentage indicates that either your page loading speed is slow, or is irrelevant.
To cut it short, Google knows what sites are loved by users and is interested in the user finding the information they need. Thus, it directs the user to the site where he/she could do it. If the user stays on the site, this means Google was right with its algorithm, and it will do it again with other users.
You may have a good site with the best design and precious information, but if your loading speed is slow, Google will not give you high traffic. Google loves fast-speed sites because it only benefits when it offers users sites with relevant content.
Thus, if your website loading speed is low, Google won't bring traffic to it. Even if you are a genius marketer, your potential customers will leave your Shopify store and not discover the product you sell if the loading takes too long.
The image below shows the likelihood of a person leaving the site as the loading time increases.