It is because you don't understand the nature of bitcoin or it's colorful history with third party services like Coinbase. The question is a good one and not at all unreasonable if you understand bitcoin. The system is supposed to be trustless, and one aspect of this is that you don't need a trusted third party to conduct safe and fast transactions with another individual. Another aspect is that you don't have to trust someone else to hold your money, but then of course the security is up to you, which has so far been something of a problem.
As others have mentioned, multi-sig addresses are one part of the solution (doesn't BitGo support these now?), and another is potentially a hardware solution. But the current Coinbase offerings are inadequate, and those types of solutions will eventually be replaced or people will continue to lose their money when they trust someone else with their private keys.
There is no insurance for stolen, hacked, or otherwise lost keys. In the banking system, when money is "lost", the loss is spread out among everyone, which is nice if you were the affected party but is a pretty raw deal for everyone else (cf. banking crisis of the past 5+ years). When bitcoins are lost, there is no recourse.
It is because you don't understand the nature of bitcoin or it's colorful history with third party services like Coinbase. The question is a good one and not at all unreasonable if you understand bitcoin. The system is supposed to be trustless, and one aspect of this is that you don't need a trusted third party to conduct safe and fast transactions with another individual. Another aspect is that you don't have to trust someone else to hold your money, but then of course the security is up to you, which has so far been something of a problem.
As others have mentioned, multi-sig addresses are one part of the solution (doesn't BitGo support these now?), and another is potentially a hardware solution. But the current Coinbase offerings are inadequate, and those types of solutions will eventually be replaced or people will continue to lose their money when they trust someone else with their private keys.
There is no insurance for stolen, hacked, or otherwise lost keys. In the banking system, when money is "lost", the loss is spread out among everyone, which is nice if you were the affected party but is a pretty raw deal for everyone else (cf. banking crisis of the past 5+ years). When bitcoins are lost, there is no recourse.