N Ways of Get Bitcoin Lost
Ways of stolen by hackers:
Wallet with trojans;
Capture unencrypted wallet data;
Capture password by listening to keyboard;
Capture server wallet password by listening to network;
Capture private key by listening to RAM;
Change payment target address of server wallet;
Dictionary cracking of brain wallet;
Brute-force cracking of account in exchange center;
Invade exchange center or server wallet to steal coin or capture password.
Ways of stolen by non hackers:
Fishing emails;
Steal cellphone with Bicoin wallet;
Steal or peep brain wallet or paper wallet;
Ways of get lost by holder himself:
Wallet encrypted, password forgotten;
Wallet not backuped,computer fails;
Wallet not backuped,wallet wrongly deleted;
Wallet not backuped,cellphone lost;
Wallet not encrypted,wallet file leaked to others;
Wallet not encrypted,cellphone lost;
Wallet not encrypted,computer sold or donated;
Brain wallet, forgotten;
Paper wallet, lost or broken;
Ways of get lost by exchange centers and server wallets:
Site disappears with all coins;
Site swallows all customer's coins and set excuse as hacker attack;
Hacker invades to system, steal coins;
Insider stealth;
Program BUG,lose private keys;
Program BUG,messed up of customer accounts;
Program BUG,send coins to some address for mulitiple times ,and cause balance loss;
No remote backup, server fails;
No remote backup, wrong operation deletes private key or user account;
Cold storage not encrypted, private key leakage, coins stolen;
Cold storage encrypted, password holder forgets password;