Hi,
I have been doing some research and found out the cause, the Shopify Speed Report. You can find the topic here; https://community.shopify.com/c/Online-Store-Speed/Online-Store-Speed-Report/m-p/908894#M390
Shopify runs the speed report using a Google Developer tool (the Google data centre is based in Council Bluffs, USA) which tests 3 pages, Homepage, a popular collection page and a popular product page. Shopify then compares this result to other similar Shopify sites. This test is run daily!
For some sites this is not a problem, but for some smaller sites this can screw with your analytics and conversion rate metrics. If you get 3000 hits a day, 3 extra visits is not an issue - it’s only 0.1%. Not every site is as big as that. My site is small and got tested twice today (15th Nov) for some reason. If you use Google Analytics you can exclude these visits from the report. I do not trust Google with my data as I have caught them doing things with my data before, and these visits are messing with the analytics in Shopify.
So if this feature is negatively affecting you, make sure to reach out to Shopify and ask them to turn it off.
Better yet ask them to give you, the store owner, the choice of when or if your site is tested. Manually, Daily, Weekly, Monthly or Annually.