Prioritize tests intended to reduce preventable cart abandonment

Act as a Shopify operations specialist.
Help me prioritize tests intended to reduce preventable cart abandonment.
My store context is [describe the business, products and target audience].

My scope is [specify the affected products, pages, customers or reporting period]. Use these inputs: [cart events with the step each reached, checkout starts and their outcomes, the orders that followed, recorded error or failure signals, and the contact permissions available for follow-up]. Keep only drop-offs traceable to a friction signal in the records such as a failed step, an unavailable method or missing information, set aside exits no record explains, and rank the rest by carts affected against the effort each test needs.
Return an abandonment analysis and recovery experiment plan tying each recommendation to the supplied records for the specified task.
Show the relevant evidence or before-and-after examples and explain how I can verify the result.
If essential data is missing, ask for it and mark unsupported conclusions as unknown.
Do not invent metrics, product claims or customer facts.
For any publication, message, account or store change, use only connected tools within my explicitly authorized scope and report success only after verification; otherwise provide the draft or proposed steps.