Business is all about flows, and flows are all about data.
An IT supported flow has to work with data objects, and how these are designed will determine the complexity and scalability of the flow model:
Since old we've used comprehensive chunks of data for presentation which has led us to keep dissimilar rigid buckets for capture, storage and flow - documents, forms and accounts.
Thingamy sticks to finite data-objects for capture, storage and flow, then rearranges finite data into chunks for presentation later.
A bucket-passing line grows complex and error-prone fast.
A river of the smallest finite objects, like molecules of water, is not complex, only capacious.
Keep empty buckets of different size next to the river and fill when need be.