Success in business is all about contacts. You never know where the next lead is going to come from, so it’s vital that you meet as many people as possible to keep widening your network. It’s a numbers game - the more people you know the more probability that you’ll be recommended to further contacts.
It’s also a bit like doing your own PR - the more trusted connections you have, the more endorsees you have promoting your work. Always say yes to an intro to a new contact - you never know what doors it might open.