Like any other reasons on the digital world, losing your password or make mistake in your transaction then you will lose your funds or the account itself forever with no chance of getting it back. Cryptocurrencies are extremely serious and there's no second chance at all, so make sure to take extra careful to everything you do with your wallet. Once locked then it's a good bye to your account. To make worse, your cryptocurrency wallet are easy to rob compared to a what bank has. For instance your wallet is open on a computer then anyone has access with it, your overall balance could be washed out without any trace. Even Law enforcement at less than NSA level is not able to help out unless the thief itself is sloppy beyond belief because of its convenience of moving the funds to any cryptocurrency through anonymous transaction makes tracking nearly impossible to those individual that has no access to the real time worldwide electronic monitoring system which is no one is going to allow use in case of a stolen cryptocurrency.