Guitar signal travels a lot before it hits your ears.
Guitar signal is generally picked by guitar pickups. Here, physical movement of the strings are transformed to electrical signal by pickups. This signal is very weak. Either it is a passive pickup or active, this signal is not audible or in other words it cannot drive a speaker cone.
This signal needs to be amplified by amplifiers in order to drive the speakers. So that we can hear it. But is it pure amplification what we need? What we got used to hear on all those great records?