2009, mobile networks class. We were studying how TCP handles packets lost over 3G: the network detects the loss, replays the packet, and the transfer survives a radio link that drops things all the time. Someone asked the obvious question: why not just make the radio link reliable in the first place? The professor's answer became the soundtrack of that semester: there is no free lunch. Reliability over 3G is not free, it is paid for in retransmissions, latency and battery. The cost never disappears. It just moves to wherever you are not looking.
I now run engineering at a no-code app builder. Every pricing decision I have seen from the inside since, his sentence explains better than any business book.
Here is the version of it nobody puts on a landing page: you can build an app for free anywhere, and you can ship one for free nowhere.
The asterisk every vendor knows by heart
Search "free app builder". Every result promises an app for free. Every vendor behind those pages knows exactly where their free tier ends: right before the App Store and Google Play. Build for free, preview for free, then the store gates close and the pricing table appears.
