Why Good Products Matter
Good products make a philosophically positive difference.
Good products mean, by definition, giving people what they want.
For example: Now you can talk to your grandparents, who are a hundred miles away, IN REAL TIME! Now you can see a picture to help you relive the moment with your niece was born. And so on.
Should you care about giving people what they want?
Well, how about the opposite: should you care about taking away something people already have and enjoy? This is called stealing, interestingly. Steve Jobs is the opposite of a robber.
Which is probably why successful societies reward these opposite-of-a-robbers. As Paul Graham has said, "Let the nerds keep their lunch money, and you rule the world."
But wait, it gets better! Innovators aren't only rewarded financially; they also receive social capital. For example, Paul Graham bootstrapped Y Combinator with the social capital he received from his successful writings. Joel Spolsky and Jeff Atwood made the same play with StackOverflow.
These are all virtuous cycles. Empirically they're very successful.
Just remember: even though these economic and social incentives encourage people to create great products, there's a more fundamental reason to do it. Good products help people lead better lives, and that's a very precious thing.