Have you ever wondered why cars with automatic transmissions have tachometers? First, let me say that I have never fact checked this. But, what I heard, many years ago, when the smaller cars began flooding the market, was that, because they run so quietly, new owners would think they had stalled out at red lights and try to restart them, thus damaging the starters and/or flywheels. The manufacturers discovered it was more prudent to include a tachometer, which indicated the engine was running, than to have unhappy customers lining up for expensive parts replacements.