Understanding Blank Product Fields
Blank does not mean zero
An empty Min, Max or Step field tells Deviking MinMaxStep to look for the next applicable value.
The lookup order is:
Product → Global → WooCommerce default
For variable products, variation values are checked before the parent product.
Why this matters
This lets you maintain a clean configuration. If the whole store uses Step 5, you can keep Step empty on products and override only the exceptions.