 Solution

Constructing channel implementations, decorators and adapters allocates software objects that hold state and references to other software objects. As configurations and temporary processing chains are replaced, some old software objects become unreachable. A typical Scala program on a managed runtime relies on garbage collection to recycle that storage; otherwise unreclaimed allocation can exhaust the available heap memory.

A reachable wrapper keeps its wrapped component reachable. Sharing a channel among several wrappers can extend its lifetime until all relevant references disappear. Many software objects alone do not imply that collection can free them: if the program deliberately retains every channel, those software objects remain live. The reason garbage collection is useful is repeated allocation combined with changing reachability, not an assumption that the integer-returning apply operation allocates a fresh channel on every call.