Hello @MarcPartsss,
Thanks for sharing your question with the Klaviyo Community!
I would suggest checking to see if you are running into any integration issues. From my experience, Checkout Started events that are not recorded consistently are typically caused by an integration issue such as if there were any syncing issues between your ecommerce platform and Klaviyo.
Also keep in mind that for contacts to trigger a Checkout Started event, the contact must be cookied. For this to happen a contact can fill out a form prior to heading to the checkout page or even enter their email as part of their contact information and move onto the shipping page which would record the email address and cookie the visitor.
Lastly, I would question weather you have a single step or multi-step checkout page. It is a known issue where having a single step checkout page may hinder the Checkout Started event from recording. I explained this in more details in a past Community post which I’ve included below:
I hope this helps!
David