Thats just the shifter cable , because of the kink where it exits behind the motor[straight route ], and also faster to change as it does not last very long .
If its muddy there is usually water around [pond /puddle /creek etc] i wipe the bike with a wet rag and poke the mud off with stick or something , and thats it , no hosing no pressure washing ..
Not just Giant , pretty much all will have same issue , i have 3 different bikes , all have cut out , main cause was magnetic/high iron dust , on wheel magnet, other was battery moving around in frame[glued rubber sheets to make it tight], and other was dirty conections , PTFE spray seems the...
I v been riding and racing one for a year now and 100% agree on your findings, have made dozens of mods just to keep it on the track, so far unbeaten no mater who turns up to race , even on $15000 top end bikes, crazy over powereded motor with terrible everything else..:sick: