The image most people have of a bitcoin theft is that of a genius hacker breaking a code. That has never happened. The network's cryptography has not been breached even once since 2009. What happens every day is much simpler: someone convinces a person to hand over what they have, or the person loses what they stored on their own.
Losses fall into five categories. Each has a habit that prevents it, and the five habits fit on one page.
The first is giving away the seed. No one takes it from you: you type it in. The request comes with the face of someone helping — a support call because suspicious activity was detected, a recovery site that appears before the real one in the search engine, an app downloaded from the official store that was fake. In February 2021, a Philadelphia resident lost 17.1 bitcoins to an app posing as the Trezor manufacturer, which was available for weeks on Apple's App Store. The habit: the twelve words are typed into the app you opened, never the one that came to you.
The second has no one to blame. It's losing the note: fire, moving, cleaning, the drawer someone emptied without asking. Paper kept in one place is just one domestic accident away from disappearing. The habit: two copies in two different places, and a test restoration before you need it. A backup that has never been restored is not a backup, it's a hope.
The third doesn't seem like a bitcoin loss, and it's the biggest in terms of money: giving money to someone who promises returns. In August 2021, the Federal Police arrested Glaidson Acácio dos Santos, owner of GAS Consultoria in Cabo Frio, who promised 10% per month and gathered tens of thousands of clients. There was no operation behind it: the returns for those inside were the deposits from those who had just entered. The habit: high, fixed, and guaranteed returns don't exist. The person paying your 10% is the one behind you in line, until the line ends.
The fourth is the promise to multiply. On July 15, 2020, about 130 verified Twitter accounts — Barack Obama, Elon Musk, Joe Biden, Apple — posted the same offer at the same time: send bitcoin to this address and receive double back. In a few hours, the address had collected over $100,000. The habit is arithmetic: anyone who has money to return double doesn't need yours, and no bitcoin transaction returns on its own.
The fifth has no scammer, no rush, no mistake. It's dying without leaving the way. If no one knows the wallet exists, or knows but has no idea how to access it, the coins remain in the ledger forever, visible to the whole world and out of everyone's reach, like the hard drive from Lesson 1. The habit: someone trustworthy needs to know it exists and where the instructions are — not the words, the instructions. The intermediate track has an entire lesson on this plan.
Four of these five have a common trait, and it is the most reliable alarm there is: urgency. The scam needs you to decide now, before telling anyone, before checking, before sleeping. The offer expires in ten minutes, the account will be blocked today, the price is only until the end of the day. No real decision gets worse if you wait until tomorrow morning, and no serious institution works on that clock.
What makes these mistakes different from all others is what closes this track: there is no refund, no support, no authority to turn to. The same property that prevents a government from confiscating your money prevents anyone from returning it. Freedom and responsibility are the same piece seen from two sides.
You already know how to use it without getting hurt. Now you need to know why it works — what exactly a private key is, how a number becomes an address, and why no one can guess yours. That's the subject of the next module, and the beginning of the intermediate track.