The vast majority of 2.4g sets do have failsafe built in and it's important to set this correctly by following the manufacturer's instructions. The only one I know of that sets failsafe positions when you bind is the Spektrum sets. Most others, it is a default setting which may not be what you'd set yourself. As others have said, set it to minimum throttle or 'off' position and everything else to neutral. All ESC's do have a 'failsafe' built in, so that they stop a motor on loss of signal, which is fine for 27mHz and 40mHz sets, but not for 2.4g sets, as they will still give a signal out if no transmitter signal is received.