This applies to all price updates and price reverting / Rollbacks.
If some products were missed from the expected update, check the following.
Be sure you selected all products matching your criteria.
Filtered by Collection - Make sure you selected All Products
Filtered by Tag - Make sure you selected All Products
Searching - Make sure you selected All Products
Check that your products are in the CSV report. History > Reports Column
Check that your products or variants exist in your store and are with a Published Status.