US journalist Mark Frauenfelder lost access to a wallet that stored bitcoins purchased in early 2016 for three thousand dollars, a little more than seven bitcoins in total. Observing that the dollar equivalent of bitcoins is growing immeasurably, he happily purchased the Trezor hardware wallet. The journalist wrote the 24-word password on a piece of paper and placed a desk in a secluded drawer. On duty, Mark had to fly to Japan and took his wife with him. Being a suspicious person, he decided to put the words of access to the wallet under the pillow of his daughter in case something happens to the spouses, then let the bitcoins go to the children.

Upon returning home, he did not find the cherished words under his daughter's pillow and realized that the houses were cleaned, and the note was thrown into the trash. Mark, no matter how he tried, could not remember the password. It was possible to make a combination of cherished words after six months, and during this time three thousand dollars turned into thirty (!).

By the way, 20% of existing bitcoins are stored in wallets whose owners do not have access to them. According to estimates by the analytical company Chainalysis, which studies blockchain technology, there are now more than 18.5 million bitcoins in the world. However, 20% of them for a total of $140 billion are on lost or blocked wallets.