1. Inspect identifiers
Confirm that every parent has a unique SKU, every variation has a unique SKU, and the Parent field matches its parent SKU character-for-character.
2. Verify exact headings
Use WooCommerce recognized column names like Type, SKU, Parent, Published, Attribute 1 name, Attribute 1 value(s), Attribute 1 visible, and Attribute 1 global.
3. Confirm attribute coverage
A variation Size=XL must appear among the parent Size options. If the parent lists only S, M and L, the new variation may not behave as expected.
4. Re-check the actual import log
WooCommerce reports skipped rows and reasons. Existing product SKU conflicts, unpublished variations, missing price values or mismatched parent rows can explain apparent success with missing entries.
5. Back up and stage
Never repeat a failing bulk import on a production store without inspecting reports. Test a parent and a few children first.