Why ATO model cannot contain PTO components.?

Summary:

Why ATO model cannot contain PTO components.? As mentioned in the whitepaper:CTO – Configure to Order

" a pick-to-order model can contain assemble-to-order components, but an assemble-toorder model cannot contain pick-to-order components"

Can someone help to understand this statement? What is the reason behind this restriction?

Reference : Doc ID 2257314.1

Document Name: CTO Setup Technical Reference

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