  We analyze the average fidelity (say, F) and the fidelity deviation (say, D)
in noisy-channel quantum teleportation. Here, F represents how well
teleportation is performed on average and D quantifies whether the
teleportation is performed impartially on the given inputs, that is, the
condition of universality. Our analysis results prove that the achievable
maximum average fidelity ensures zero fidelity deviation, that is, perfect
universality. This structural trait of teleportation is distinct from those of
other limited-fidelity probabilistic quantum operations, for instance,
universal-NOT or quantum cloning. This feature is confirmed again based on a
tighter relationship between F and D in the qubit case. We then consider
another realistic noise model where F decreases and D increases due to
imperfect control. To alleviate such deterioration, we propose a
machine-learning-based algorithm. We demonstrate by means of numerical
simulations that the proposed algorithm can stabilize the system. Notably, the
recovery process consists solely of the maximization of F, which reduces the
control time, thus leading to a faster cure cycle.
