My SGS 1-35C had flaps for glidepath control. I have removed flaps on approach for that glider.
Glider, pawnee, 172, arrow - most of the end of the flap travel is drag, not lift. If you go to power up and the power is not there, do you give up? Personally I have played with them all.
You can argue that needing to change flap settings, or power settings, or sideslip is a display of poor planning. It is wonderful when you plan well enough, and that the conditions are predictable enough that you don't have to do anything. Often what separates the pilots from the aircraft drivers is how they react when things don't go as planned.