These are blocks that have been received but cannot yet be attached to the main chain due to missing predecessors. The necessity to iterate through the entire collection of such orphan blocks stems from a specific technical constraint: the short IDs, which are critical for identifying and processing these blocks, are not determined until the compact block is fully retrieved and decrypted. This means that predicting which blocks will be needed ahead of time, based on their short IDs, is not feasible.

The inability to precompute short IDs before acquiring the complete compact block enforces a methodology where each block in the orphanage must be examined. This exhaustive search ensures no potential connections are missed, which is essential for maintaining the integrity and continuity of the blockchain. The process underscores the complexity involved in handling blockchain transactions and the dynamic nature of block validation and integration. It highlights not just a specific technical challenge, but also illuminates broader considerations in blockchain architecture relating to data retrieval, verification, and the seamless incorporation of new blocks into the chain.