class RequestQueue finish()的机制 mechnism

[panq-jack]

void finish(Request<?> request) --> last line: mCacheQueue.addAll(waitingRequests);

how to understand this? why we transfer all requests in waitingRequests to cacheQueue this time
instead of put them to cacheQueue originally created? u know, both action can add the request to NetworkQueue if can't get desired cache;?