...but when that 150-250 amp surge is trying to turn your engine over...that "short ground wire" becomes a:
battery neg terminal>ring terminal>wire>ring terminal> sheetmetal>series of spotwelds>sheetmetal>series of spotwelds>sheetmetal>spotwelds>sheetmetal> spotwelds>sheetmetal (now we are at the pass front unibody rail)> ring terminal>wire>terminal>groundbolt>starter motor negative windings
or it can flow:
batt>ring terminal>high grade fine strand copper wire>ring terminal>ground bolt
try to guess which is the one thats gonna flow a large amount of current with the least amount of voltage drop
