[alimbada]

Or:

1- Someone bought ETH for a ridiculously cheap price during the presale and forgot all about it (https://etherscan.io/address/0x7d551397f79a2988b064afd0efebe...)

2- Realised two years later how much it's worth

3- Decided to cash out having no prior experience of how stock/ForEx/crypto exchanges work, i.e. they were ignorant of the consequences of dumping that much ETH on one exchange in one go

4- Which then triggered a cascade of stop losses and margin calls.