Publish 7 April 2021
Speed is Priority
Like musical chairs, Google periodically changes internal algorithms. If you do not keep up, a website that enjoys first-page organic search results can find itself way beyond page 20. When the music stops again on May 1, 2021, will your website have a seat on the first page? Ranking goes up or down in relation to how fast your web pages load. 
Google bases performance scoring on its tool called Lighthouse analytics that measure PageSpeed. Shopify now integrates your score on the Themes page within admin. Geared toward e-commerce, representative pages are Home, Collection, and Product pages. But Lighthouse examines more. Score basis is 28-day aggregate experience of all pages served from your site.
Your personal computer configuration may be faster than most. The Google test runs from remote devices using a Chrome browser. A great score is between 90–100. A good score is between 50–89. Cellular mobile pages can take up to twice as long to load as desktop computers with a hardwired internet connection. So Lighthouse provides variable mobile and desktop scores. 
As performance aggregates over time, it can take up to a month for Google to recognize changes and update your site score. This also gives your server opportunity to cache static data in response to structural site changes.
Some site optimizations are beyond your control. When large swaths of the internet went down, service providers were switching to backups. In another instance, Shopify rolled out major user interface enhancements to the merchant admin controls. During this transition, page loading increased by orders of magnitude for a day or two. This skewed 30-day average speed.
Optimizing Site Performance
Small adjustments like prioritizing and deferring certain scripts can have a big impact. Static pages allow data to be cached for speed. Another important thing to do is optimize the size of images. 
According to Google, a one-second site speed improvement can increase mobile conversions by up to 27%.  Shopify themes have aesthetic options that may increase page load times. The theme for this site has the following options for Collections:
- Display Collection header image
- Set number of grid thumbnail images
- Hover to display alternate image
- Recommend products
- Show browsing history
- Display Collection footer
Some of the options include subsets of more choices that include product description display. There are also global options for animations. Every Shopify merchant controls which sections are visible on the home page.
Some home page sections take longer to load than others. Make some tough choices about essential sections for the sake of Google organic search position,
As a desktop user and programming artist who is fond of bells and whistles, I initially activated most features for an average speed score of 36. This guarantees an absent seat when the new ranking protocol music stops.
I optimized all Product, Blog, and Collection images. The Blog grid display was reduced from 13 to 7. The Collection grid reduced from 16 to 12. Then I experimented with disabling alternate hover images (for half as many images), halting product recommendations, and deactivating the Collection footer. All this brought the score up a tiny bit. So then I had to tinker with the underlying code. I added an exception to activate alternate product hover images only on Collection pages. This significantly reduced the number on the home page.
Product image optimization benefits anywhere products appear, including collection pages, product pages, the home page. LazyLoad images may or may not be apart of your current Shopify theme. It improves perceived performance by only loading images within the field of view. With activation on the ClinicalPosters website, I continue experimenting with Collection page options.
PageSpeed insights provide suggestions. You can run the test three times in succession and get different scores. Focus more on the optimization suggestions than the specific numeric score.
Some script and server plugin implementation is at the discretion of the hosting platform. For other scripts, you may need to contact a contact the theme developer or a Shopify Expert.
A simple adjustment offering a significant speed boost for this site came from rearranging priority within
theme.liquid. Compressing and moving the
defer="defer" to some scripts may also help. Script ordering requires programming logic with trial-and-error.
Additional housekeeping includes identifying and correcting broken links. Assess the NoFollow areas of the website and optimize Collection paths.
Like many other Shopify merchants, ClinicalPosters currently is on a plan that shares a server with four other e-commerce sites. Their peak traffic and optimizations sometimes impact ClinicalPosters visitor performance. Very active sites might weigh the cost of the Shopify Plus plan that includes a dedicated server and more features.
As is the case with my custom theme, there may be many options that affect site performance. After going through all the code, I added an Optimize option that overrides multiple user settings for best performance. This includes things like using minimum dimensions for thumbnail images, reducing the amount of images on grids, and disabling some animations.
Whether you tackle optimizations yourself or hire an expert is your decision.  But recognize that the ideal search engine optimization position you fought hard to achieve may decline if you do nothing. Google is giving e-commerce an ultimatum: Speed up your site or lose visitors along with revenue. Are you ready to face the music?