The problem 1: QSpinBox::editingFinished() signal gets fired even if a user cancels editing via ESC button.

The problem 2 here (even worse than 1st one) that in a slot connected to the signal the "wrong" (cancelled) value is still accessible via QSpinBox::value().

i.e. when the value in the QSpinBox was 42, and the user started by typing 13 but then pressed ESC, QSpinBox visually returns to 42, BUT editingFinished() will be fired and in the slot, 13 will be read instead via QSpinBox::value() .