You can obsess about serving your customers/audience/clients， or you can obsess about beating the competition. Both work， but of the two， obsessing about your customers will take you further.

The decay of political institutions is often a result of the inability to adapt to changing circumstances, leading to rigidity and eventual decline.

世界是一面镜子，它映照出我们的丑陋。

密码学是关于在存在对手的情况下进行通信的。