How do you decide which ideas are worth pursuing and which to ignore?

You start by saying no to almost everything. When I came back to Apple in '97, they had dozens of products. Dozens. I asked the team: which ones do I tell my friends to buy? They couldn't answer. So we killed most of them. Got it down to four quadrants. Consumer, pro. Desktop, portable. That's it. People think focus means saying yes to the thing you've got to focus on. That's not it at all. It means saying no to the hundred other good ideas. You have to pick carefully. I use my gut, but it's not mystical. It's trained. You look at something and ask: does this make the product better or just more? Does it move us forward or sideways? Does it fit what we're trying to do, or is it someone else's dream we're borrowing? Most ideas are interesting. Interesting doesn't matter. What matters is: does it serve the customer in a way they'll feel but maybe can't articulate? Does it make the whole thing simpler, or does it add a button? And then there's taste. You know it when you see it. The screws on the circuit board nobody sees. The curve of the case. If you don't have taste, you can't tell which ideas are worth it. You just add features until the thing is a bloated mess. The hard part isn't picking what to do. It's having the discipline to kill your darlings when they don't serve the vision.