For the past five months I've been doing a monthly performance assessment for Repeat Customer Insights. Yesterday I just finished the one for August and saw I've been able to roughly 3x the performance across various metrics.
This assessment includes looking at how the app has been performing, finding slow spots, and taking note of areas that might cause scaling issues later on. The goal is to keep the app running fast and to improve the experience for store owners.
Now that September is here, you should already be working on your winter holiday marketing. It's also time to take a close look at how your storefront is performing.
A slow store will absolutely lose you sales and customers are expecting faster and faster websites every year.
One thing you cannot do is to rely on Shopify, your theme, or an app to make your store fast. They can (and should) be focused on minimizing their impact on your store but the responsibility for the performance ultimately falls on you.
There are many options to test your performance. From DIY (e.g. Google Lighthouse, WebPageTest) all the way to hiring a consultant.
The important thing is to start early, well before the rush, so you have enough time to learn, measure, and implement any changes.
Market to your customer's timing
Figure out how long customers wait in-between purchases and you have a key component for your marketing timing. This is the basis of the Average Latency metric and Order Sequence Report in Repeat Customer Insights.