Throughout history, thousands of bitcoins have been lost in thefts, lost private keys, simple keys and devices.
When we talked about the devices, a man had stored in a hard disk more than 1000 bitcoins years ago, he lost this hard disk in the garbage, but when he heard about the imminent climb he went to retrieve it to the landfill although it was too late by that time .
There are several cases like this but similar, it is unfortunate that many bitcoin units have been lost without mercy forever, including sending bitcoins to non-existent purses, these cases have also manifested on more than one occasion.