Just its existing network effect. A new blockchain, alt-coin, or ripple-type system can and do pop up all the time, but bitcoin has a significant network. If

Just its existing network effect. A new blockchain, alt-coin, or ripple-type system can and do pop up all the time, but bitcoin has a significant network. If someone invested in building out a new digital payment network they could overtake bitcoin. But its not getting easier every day as bitcoin adoption grows.