Except for airplanes that are refueled in the air, landing weight is always less than takeoff weight. For most jets that difference is large. Therefore, thrust required for the same performance (speed, climb rate, etc) is significantly less.
Transport airplanes are designed with enough thrust to continue to accelerate and takeoff before the end of the runway if one engine fails after a defined point (V1). Therefore, a go-around with a failed engine is even less problematic.
In the simulator, an engine failure at low altitude on the approach is a "non-event" in the 747. If it is an inboard engine and the autothrottles are engaged, the Pilots may not even notice until the generator lights come on...