Why my Shopify site's Core Web Vitals score in Google Page Insight shows as failed

As a Shopify developer who has been working with the merchants on this platform since 2017, I get asked this question a lot. While my main expertise lies with Custom Landing Page building and not with Speed Optimization, I thought of writing a simple blog article that I want to send to my clients whenever they ask me about Shopify speed optimization. 

So, if you're a merchant or a developer, I assume you've looked into Google Page Insight and saw that the Core Web Vitals are showing as "failed", and as an improvement suggestion Google have added things like "Reduce unused JavaScript".

I will give you my honest opinion regarding this issue. So, the reason most Shopify sites have this "failed" status when it come to Google Page Insight is because of the usage of apps. So if you use just a fresh theme without using any sort of app, then you'll most likely see that the Core Web Vitals are showing as "passed" in Google Page Insight.

But the problem is, if you want to have different features in your store, such as Chat widget for customer support, or Product review section that you can manage easily and do advanced stuff with e.g. sending emails to customers after 5 days of purchasing the product and asking them for a review, or adding custom pop up widget so that you can collect customer emails in order to have email marketing campaign, all these things you can do in minutes by installing an app from Shopify app store, but it'd likely cost you tens of thousands of dollars if you wanted to make these features from the ground up. There are pros and cons of using Shopify apps,

Pros,
Installing an app is a time effective and cost effective way of getting important features in your store (e.g. email marketing), for which you may have needed to spend thousands if not tens or hundreds of thousands of dollars in order to make those features by an agency.

Cons,
I think many apps including the very well reviewed ones aren't coded with page speed in mind. More often than not, they probably focus solely on providing best features possible and not focusing too much on the page speed as long as the page speed isn't noticeably bad. That's why the website's performance decreases slightly when you install an app.
The good news is that Shopify is working on this issue and they've made quite a few changes in 2021 with their Online Store 2.0 and they're taking website performance seriously and their Online Store 2.0 technology is helping app developers provide a custom feature to a client with better loading time. So we can expect the app related page performance issue to be reduced overtime.

So, basically I believe that what merchants need to mainly think about is whether their website is noticeably slow or not. If it is noticeably slow, then they need to worry about the problem and fix it by uninstalling some apps or hiring a developer in order to get consultation regarding the issue.

Lastly, I want to give two examples where two of the biggest stores in Shopify also has "failed" status in Google Page Insight when it comes to Core Web Vitals. This shows that having a "failed" status in Google Page Insight actually doesn't mean much. Majority of the big Shopify stores have a "failed" status in Google Page Insight as far as I know, and they are making billions and billions of dollars each year. So this Core Web Vitals metrics is just a vanity metrics for most stores, unless you're a super big store like Amazon and having even 0.5% page speed improvement will mean having millions of dollars in extra revenue. Only then you can justify spending money on this kinda issue.


Here are the sites that I've mentioned. You can look up even more highly successful stores in Shopify and you'll most likely see that their Google Page Insight score shows as "failed". So here are those stores,
- Fashion Nova
- Colour Pop

See their Google Page Insight,
https://pagespeed.web.dev/report?url=https%3A%2F%2Fwww.fashionnova.com%2F
https://pagespeed.web.dev/report?url=https%3A%2F%2Fcolourpop.com%2F

Author,
Blanc Roy | Founder at Cepta Tech