Why aren’t Forced Approached always successful?
The student usually does well until final approach. It doesn’t matter what technique or pattern is used to get to the final approach. When rolling out on final for the forced approach, the focus must be on the landing aim point. Just like a final approach for a normal landing. If everything has gone well to this point, the landing should be assured. The aim point is now critical not the glide speed. You never want it low as the forced approach will not be successful. If the airspeed gets high you have options. You can start to lower flap in stages. For most light aircraft, each notch of flap will reduce 10 knots. If still high, you may slip. If the airspeed is still high, it will decrease very rapidly when you flare for landing without power and full flap.
The aim point is crucial. With an aim point. you will land where you want.