Understanding Credit Usage for Clay's Enrichment Use Case

Hey Clay S., we ran the following table to test the full capability of Clay for enrichment use case and we wanted to understand how 28 credits per row has been decided? https://app.clay.com/workspaces/438611/workbooks/wb_0sxqzttnH8aAXzQxDSF/tables/t_0sy005mYrERZTE6Rqui/views/gv_0sy005nhgGDn4qenVKx Our hypothesis: If a lead has already been enriched with certain fields (e.g., title) using People Data Labs, and we later request additional fields (e.g., company) for the same lead using the same provider, should credits be charged again? Ideally, once a lead is enriched, shouldn't the provider return any additional requested fields without consuming additional credits in the same table as a part of waterfall enrichment? However, in the above table, each waterfall took its own credit and cumulative pushed 28 credits per row.