Below the nesting cap: the chain is longer than this reader follows.
The slot re-enters a configuration already open on this path.
The node budget for this top-level load was spent before this slot.
The slot is not a structural-load reference ($, an inline value, or a different IFC class).
The referenced expressId is in no index — a dangling reference.
The referenced record is indexed but did not parse.
Why one
Valuesslot carries no nested load.The first three are our bounds firing — the file may hold more than we agreed to read, and StructuralLoadConfigurationInfo.truncated is set. The last three are the file's own data: there is nothing further to read, so they are not truncation.