I recently came across a case that made me break out in a cold sweat—not because the incident itself was particularly bizarre, but because situations like "internal operational mistakes within families" leading to asset loss are actually very common. Anyone who has experienced several market cycles can confirm: in nine out of ten crypto loss tragedies, the root cause points to the same issue—"lack of security awareness."

**First Pitfall: The Line of Defense of the Mnemonic Phrase**

There's a detail that hits especially hard. When a user’s family member copies the mnemonic phrase, essentially, they are exposing the account key to the online world. Why is this so dangerous?

Hackers now use highly industrialized toolchains. Many so-called "convenience tools" like browser plugins or "airdrop helper programs" secretly include clipboard monitoring modules. Once you copy the mnemonic phrase, the hacker’s server immediately receives a signal—and then automatically scans, locates, and transfers funds. The entire process can take just a few seconds.

Even more frightening is the cloud synchronization line. Storing the mnemonic in chat apps? That’s equivalent to backing up your password to a cloud server and hoping hackers won’t find it. In reality, once your email or cloud storage is compromised, hackers searching for "mnemonic" or "private key" keywords can precisely locate your assets within minutes.

Another often overlooked risk: incomplete cleaning of old devices. Deprecated Android phones may still retain cached wallet app data. If this device is connected to public WiFi or a home network with unchanged passwords for years, it becomes a hacker’s ATM.

**How to Truly Protect Your Mnemonic Phrase?**

The most straightforward solution: use a fireproof and waterproof metal card (costs are low, just a few dozen yuan), engrave the mnemonic on it with a pen, and store it in two completely isolated physical locations. One at home, one in a bank safe deposit box. Even if one location suffers an accident, the other can still restore access.

Absolutely forbidden actions: screenshots, WeChat forwarding, email backups, cloud sync. Every time you do any of these, it’s like leaving a breadcrumb trail to your assets on the internet.

**Second Pitfall: Family Members’ Operational Permissions**

This topic is even more tricky. Legally, it may be hard to distinguish whether a theft was by a hacker or a family dispute, but the more fundamental issue is: most ordinary people simply don’t understand what a mnemonic phrase represents.

In your spouse’s eyes, it might just be a meaningless string of words. In your parents’ view, digital assets are not really "assets"—they haven’t developed that psychological understanding. This cognitive gap is often more deadly than technical vulnerabilities.

You can’t expect every family member to have cryptography knowledge. But what you can do is: restrict their operational scope. Set up two-factor authentication for large withdrawals, separate daily management permissions from emergency recovery permissions. Simply put, give family members read-only access rather than full operational rights.

**Third Pitfall: Environmental Cognitive Bias**

Many experienced users also make a mistake: equating "the security knowledge I learned in security communities" with "the security common sense everyone should know." That’s not true. Your elders at home may not even realize that a seemingly harmless financial app could secretly monitor their clipboard.

Therefore, truly effective defense isn’t about individual caution alone, but about layered systematic protection—multi-signature wallets, hardware wallets, cold storage, permission separation. Each layer should have independent risk controls.

One last point: this is not alarmist talk. Every month, tens of thousands of people lose assets due to these basic mistakes. The difference is that some people cut losses in time, while others fail to notice for various reasons—until a certain moment when they realize the problem. Instead of waiting for that moment, it’s better to build your defenses now.