There may be reporting bias going on. I suspect a high percentage of people who lose BTC by themselves will report it in a forum, since, as far as they know, their case might have unique details in which a more knowledgeable person might find a solution. But a low percentage of people who lose BTC due to an exchange hacked will report it, since the information they need is already in news and blog posts all over the web.

Exactly. And the top notch exchanges keep everything in cold storage AND they take out massive insurance policies on it. Keep coins there unless we are talking millions of $ worth.

The insurance coverage is limited and doesn't cover theft of individual accounts.

No exchange has a full insurance on their cold storage. Not a single one.

Honest question. How is this possible? Isn't it as simple as copy and pasting the public address?

Among other things, there's malware in the wild that rewrites public addresses when you paste them into the major exchange's "send coins" forms.

https://www.investopedia.com/news/new-bitcoin-malware-change...

Take ETH and ETC for example, they both have the same address format and accidentally sending from one chain to another results into your crypto being locked away forever.

You could ask this guy: https://etherscan.io/address/0xa8f889a066519ffb552a571d553b8...

Looks like he copy-pasted a corrupt version of the address. There are three transactions to this destination, from different exchanges.

I've had an instance where the withdrawal to my wallet seemingly didn't even make it to a block on the chain. This happened on Coinbase and took over 2 weeks to resolve. With their non-existent support I pretty much considered that money lost until the whole thing finally got resolved. But I can definitely see somebody fat fingering the wallet address being one of the bigger reasons.

Well, you’ve also got to keep track of the private key...