Imagine, Peter wants to talk with Mary. But Peter does not know Mary. Peter finds IntroHub. On IntroHub Peter finds Paul who listed Mary as potential Intro. Peter dares to try and requests an Intro to Mary via Paul. When Paul listed Mary he knew that he got 5 business days to accept or decline the Intro request. When Paul listed Mary she knew that Paul may ask about Intro requests he might get in the future. Why should Mary want that? Because Mary can promote herself on IntroHub. Either by herself or via Paul.
Now, when Paul is accepting the Intro request, it means that Paul asked Mary to talk to Peter and that Mary actually agreed to get her contact information to be forwarded upon Peter's Intro request. Declining the Intro request means that either Paul or Mary did not want to accept the Intro request. For whatever reason, this is fine. In either case real people acted upon their promise. Their promise was to act, one way or the other. Maybe Peter gets even a message why neither wants to talk to him. Peter got feedback from real people. That is something. Way better than shooting right into the blue and never knowing if Peter's Email to Mary ended up in some spam filter or just got lost in the ether.
Let's say Paul does not react to the Intro request Peter made on IntroHub at all within 5 business days. Then Paul loses all network benefits of IntroHub for 3 months. Not even Mary could introduce someone to Peter during that time. Uh, that hurts. So why should anyone want to participate on IntroHub? Simply because any wantrepreneur needs connections to people other wantrepreneurs and entrepreneurs already have. The whole point of IntroHub is do be a healthy member of the network. The point is to be a good citizen. The point is the selfish gene.
And now let's connect and destroy the idea pretty please. Worst case we go and build it. <3